I generally put mine on top of my blush, unless it is one of the darker ones then they are used for contour and/or blush. Depending on the color, I put it all over my cheeks or just on the high planes. With Porcelain Pink and Lightscapade (two of the lightest), I like to also continue them up my cheek bones and on to my temples as well. The 188 is my go-to brush since it helps me control where I put my MSF.