The uppermost or most important surface; the face of the cloth designates the right side, the one that will be seen after the making process. Some cloths are double faced, with two equally valid sides, or faces. Some have only one viable face, say with suede, velvet or a bouclé weave.
The underside of any print and many weaves is softer than the top side, so for a vintage look the back side may well be the side you prefer to see. For the purpose of making up, following instructions, the face is the side that you choose to use, whether it’s technically the front or the back.