Clean your brushes after each use. I do not enjoy cleaning brushes (who does?) but I do love, love a nice brush in beautiful condition so I take the time, every time, to clean my brushes after I use them. I do not roughly mush the bristles in the bottom of a jar or cup…I gently push the bristles around between my fingers, on the palm of my hand, on the bottom of the sink or on a metal mesh I keep in my sink–key word being GENTLY. I do not recommend leaving a brush soaking in water or cleaner very long. All CeCe Caldwell’s Chalk + Clay Paints products are water based so none need any kind of mineral spirit or paint thinner and I personally do not recommend using anything stronger than dish soap and vinegar when cleaning any brush (and if you make a habit of cleaning your brushes after each use you shouldn’t ‘need’ anything heavier) . Synthetic brushes do not need to be conditioned with oil soap and can be cleaned with just water or with dish soap and/or a bit of vinegar.