4. Use Small, Sealed Bags
This is perfect for girls what take a lot of make up with them! Don't leave yours lying at the bottom of your bag, if a lid comes off the contents will go everywhere and will stain (and ruin) the inside lining of the bag, as well as colour-leaking onto everything else you have in there.
To avoid this problem, put your essential cosmetics inside a small, sealed bag (or a couple, if you have lots to take with you). This will keep them all in one easy and convenient place and make them incredibly easy.
And the best part? If a lid does come off it will only leak inside the sealed bag and not touch the interior or anything else you have inside.