Wash up.
Great makeup starts with great skin. It is so important to remove your makeup before you turn in for the night (maybe even before taking off your bra and putting on the sweats). I use a damp Norwex Body Cloth to remove my makeup (bonus: it exfoliates too). Just dampen with warm water and wash. If you have a regular cleansing routine, you should still keep up with that just as you did before.
Every 2-3 applications, I will also swirl my brushes in the damp cloth as well to remove makeup residue and keep them working flawlessly. You want to keep them clean to avoid streaking of your makeup, and offset the growth of bacteria. For a deeper cleaning method, see the information below about SEINT brush cleanser.