Common Eyelash Extension Mistakes and How to Fix Them

Course: Eyelash extensions course from A to Z · Module 10 of 10

Every lash artist makes mistakes when starting out; what matters is spotting them early and understanding where they come from. In this final module we go through the most common eyelash extension mistakes (stickies, irritation, poor retention and messy direction), how to prevent and fix them, how to get the most out of mannequin practice, and how to keep developing your skills.

Module objectives

Identify what causes stickies and how to separate them without damage.
Tell irritation apart from a possible allergic reaction and know how to respond without giving medical advice.
Troubleshoot poor retention by checking environment, adhesive, technique and aftercare.
Correct direction and placement problems.
Structure effective mannequin practice and plan your ongoing training.

Mistake 1: stickies

A sticky happens when an extension, or adhesive, joins two or more natural lashes together. Besides being uncomfortable, it stops each lash growing and shedding on its own cycle. Lashbase and London Lash list these causes:

Incomplete isolation, especially around baby lashes. London Lash calls baby lashes stuck underneath an extension the most common type of sticky, and the easiest to miss.
Too much adhesive: the more glue there is, the more likely it is to catch a neighbour.
Not letting the bond set before moving on, or an adhesive that is too slow for your pace.
Criss-crossed fan bases or extensions sitting raised off the natural lash.
Crowding: working lots of lashes in one spot, or squashing lashes into wet glue.

How to prevent and fix them

Isolate in layers, using light pressure so you don’t squash the lashes (London Lash).
Alternate areas and eyes to give each bond time to cure; London Lash suggests leaving a gap of about seven lashes.
Slide the base into the glue dot and out again rather than scooping.
Check as you go with a dental mirror and spoolie, then lash by lash from root to tip at the end.
If you find one, hold one lash with one pair of tweezers and peel the other away with the second pair (the “banana peel” method).
Allow at least 10 minutes at the end of the treatment for checking (London Lash).

Mistake 2: irritation and reactions

Red or stinging eyes after a treatment do not always mean an allergy. Lovely, an adhesive manufacturer, distinguishes two situations:

	Irritation	Possible allergic reaction
When it appears	Immediately or within a few hours	Lovely puts it at 24–48 hours; EyeWiki says it may appear hours or days later
Symptoms	Redness, watering, stinging	Swollen eyelids, redness, itching
Usual cause	Fumes from the adhesive as it cures	Immune response to an ingredient

Ophthalmology literature confirms the risk is real. EyeWiki, from the American Academy of Ophthalmology, cites a study published in Cornea (Amano and colleagues, 2012) on eye disorders caused by eyelash extensions, and describes complications including keratoconjunctivitis from adhesive chemicals reaching the eye surface, allergic blepharitis linked to adhesive and eyelid tapes, and conjunctival erosion from tapes.

Prevention in the treatment room

Keep the client’s eyes fully closed throughout: if they are slightly open, fumes can get in and cause stinging (Lovely).
Place extensions at the right distance from the lid with a small amount of adhesive; too close, or too much glue, causes discomfort.
Check pads and tape: they should protect without rubbing the eye.
Carry out the consultation and, where appropriate, the patch test covered in Module 3.

How to respond

Don’t diagnose or recommend treatment. If the client has intense itching, swelling, pain, discharge or changes in her vision, stop or remove the extensions with remover and advise her to see a healthcare professional promptly. Record what happened and the products used on her client card.

Mistake 3: poor retention

When extensions fall early, work through the possibilities one by one. This table summarises the causes listed by Lash Jungle and Lovely:

Area	Possible cause	What to do
Environment	Humidity or temperature outside the adhesive’s range	Measure with a hygrometer and adjust (Lovely: 45–65% and 20–23°C; Lash Jungle: 50–60% and 21–25°C; your adhesive’s instructions take priority)
Adhesive	Bottle open too long, under-shaken, or a dried-out dot	Replace 4–6 weeks after opening, shake as directed, refresh the dot every 15–20 min
Adhesive	Too fast for your skill level	Lash Jungle suggests beginners use a slower adhesive
Prep	Oil or make-up residue	Lash shampoo, then primer as directed
Technique	Too little contact, poor isolation, wrong glue amount	Bond at least 2 mm, one extension per lash, small amount
Weight	Extension or fan too heavy	Reduce diameter, length or fan size
Client	Not following aftercare, very oily skin, watery eyes, oil-based products	Written aftercare; Lash Jungle also mentions pregnancy because of hormonal changes

A useful clue from Lash Jungle: if extensions pop off when lightly touched, the problem is most likely the application. Climate also varies more than you might think: in Tenerife, for example, AEMET’s climate normals give 63% average annual humidity in Santa Cruz and 73% at Tenerife North. Always measure inside your own room, and choose an adhesive from our glue and liquids range whose instructions match your conditions.

Mistake 4: direction and placement

A set with extensions pointing in different directions looks messy even if retention is good. The usual causes are a base that isn’t parallel to the natural lash, not checking the angle before letting go, and not adapting the attachment point to the way each lash grows.

Keep the base parallel to the natural lash along the whole contact area.
Work to a consistent reference angle; Lashbase uses 90 degrees to the lid and warns against wide angles in the inner corner.
Choose the attachment point by growth direction: on top for straight or downward lashes, underneath for upward-growing lashes, on the side to fill gaps (Lashbase).
Check from different angles with a mirror, and with the client sitting up at the end.

Mannequin practice

A mannequin lets you repeat isolation, placement and mapping without pressure. Recommendations from Divine Lashes and Curacoro:

Posture. Set the mannequin at roughly chest height when you are seated, arms close to your body, wrists supported and fingers resting on the mannequin’s forehead.
Real set-up. Lay out your tools as you would for a client and put a pad under the mannequin’s eyes; you can draw your length map on it.
Warm-up. Count the mannequin’s lashes with your tweezers.
More realism. Mannequin lashes don’t have layers like natural lashes; stick two strips on top of each other to simulate them.
Separate drills. Use a round make-up sponge to practise angle, direction, glue amount and fans.

A mannequin is no substitute for real lashes. Curacoro explains that training typically involves one or two models, and suggests starting with around four models afterwards to build a portfolio, photographing every angle; Divine Lashes talks about a few months of regular practice before beginners can confidently charge full price. If you are setting up your first station, our accessories and tweezers ranges cover the basics.

Training and continuing to learn

Training routes and requirements differ from country to country, so check what applies where you work. In Spain, for instance, the official Técnico en Estética y Belleza qualification (Royal Decree 256/2011, a 2,000-hour intermediate vocational programme) includes “application of false lashes, in clusters, strips and extensions” in its make-up module (0634), alongside lash tinting and lash perming. There are also many private courses. Before you choose one, check:

Whether it includes supervised, in-person practice on real models.
Who teaches it and what experience they can show.
Whether it covers hygiene, contraindications and eye safety, not just aesthetics.
What document you receive, and whether it is an official qualification or the provider’s own certificate.

To keep improving: read the instructions and technical sheets for every product you use, photograph your sets and compare them with the planned map, note on each client card the materials and map you used and how retention looked at the infill, and keep up with eye-safety resources such as EyeWiki. Also find out which local rules apply to practising in your area.

Common mistakes when practising and training

Practising on a single layer of mannequin lashes, then being caught out by real, layered lashes.
Chasing speed before clean isolation.
Skipping the final sticky check because the booking ran over.
Blaming every fall-out on the client without checking environment, adhesive and technique.
Choosing a course for the certificate alone, without supervised hands-on practice.

Module summary

Stickies: isolation, glue amount, curing time and a final check.
Immediate irritation is not the same as a possible delayed allergy; with significant symptoms, remove and refer to a healthcare professional.
Retention: check environment, adhesive, prep, technique, weight and aftercare, in that order.
Direction: parallel base, consistent angle and attachment point matched to growth.
Mannequin work with good posture and layered strips; then real models under supervision.
Quality in-person training and ongoing learning from each manufacturer’s instructions.

Self-assessment

According to London Lash, what is the most common type of sticky, and the easiest to miss?

Baby lashes stuck underneath an extension.

A client has stinging and watery eyes straight after the treatment, and is fine the next day. What is more likely?

Irritation from adhesive fumes, which appears immediately. Make sure her eyes are fully closed next time. If there were swelling or intense itching, she should see a healthcare professional.

Extensions pop off when lightly touched. Where do you look for the problem?

According to Lash Jungle, it points to the application: too little contact (under 2 mm), poor isolation, the wrong amount of glue, or an adhesive that doesn’t suit the room conditions.

How can you make mannequin practice more realistic?

Stick two strips on top of each other to simulate the layers of natural lashes, and work with the same posture and set-up you would use with a client.

Note: this online course is for educational and information purposes only and does not replace hands-on, in-person training with a qualified educator. Always follow each product manufacturer’s instructions.

Sources

Buy the course supplies

All the supplies for this course are available at Lash Canarias:

← Previous module

Course index