Are you supposed to keep the rubbery/plastic sleeves that protect the brush, or throw them away? I like that they keep my brushes in shape, but I don't want bacteria breeding in there.
I am not sure if you are "supposed" to keep them or not but I just get rid of them and make a habit of washing my brushes about once a week and storing them in a cool, dry place.
I just throw mine away. Your brushes should hold their shape fine as long as they're stored properly and when you wash them just squeeze them dry and shape them to their natural shape and lay them flat to dry. You should wash any synthetic hair brushes i.e. concealer, foundation, eye liner every day, and natural hair brushes every 3-5 months. Baby shampoo works well, it is very gentle for the brushes. HTH!
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