The key to removing eyeliner from carpet is to find the right cleaning solution. This can take several tries, because carpets and makeup both vary in composition. Tackle eyeliner stains as soon as they happen for the best chance of complete removal, and be prepared to try several different cleaning solutions before finding one that works. When you do, you may have to apply the cleanser several times, removing only a bit of the stain each time, until all of the eyeliner is gone. Remember to test each cleaning solution you try in a discreet area first, to make sure it won't discolor or damage the carpet.
Because it's formulated specifically to remove makeup, try makeup remover first. You can use makeup remover wipes or pour some liquid makeup remover onto a clean, white towel. Dab at the stain -- don't rub, as this may spread the stain. Use a second, dry towel to absorb the liquid back out of the carpet. Repeat the process for as long as at least some of the stain is lifting onto the dry cloth when you blot.
Models frequently take off their eye makeup with baby wipes because they work so well at removing eyeliner. Try blotting your carpet stain with baby wipes to remove eyeliner accidents.
Make a cleaning solution by combining 1 tablespoon of dish soap and 2 cups of warm water. Blot the solution into the carpet with a damp white towel and remove it again by pressing a dry white towel into the carpet. Repeat this process for as long as some of the eyeliner continues to lift out of the carpet.
Combine 1/2 cup of warm water and 1 tablespoon of ammonia. Try dabbing this cleanser onto and back off of the carpet to remove the eyeliner. Repeat until the stain is gone or stops lifting out of the carpet.
Distilled white vinegar is slightly acidic and removes many different types of stains. If the eyeliner in your carpet just won't budge, pour 1 teaspoon of white vinegar into 1 cup of warm water. Again, dab the mixture into the carpet with a damp cloth and blot it back out to remove the eyeliner.
When all else fails, try a dry-cleaning solvent. These solvents can be harmful to carpet backings if allowed to penetrate through the carpet, so use them with caution. Always apply the solution onto a rag and blot it onto the carpet sparingly rather than pouring the solvent directly onto the stain. Again, press a clean, dry cloth into the carpet to remove the solvent and the stain.
Although it's far more efficient and cost effective to remove an eyeliner stain yourself, it is important to know when you've been beaten. If none of these solutions work, consult a professional carpet cleaning service about removing the stain rather than risk damaging the carpet.