How To Stretch Watercolor Paper With Tape. Let the paper dry overnight. Lay the board on a flat surface and wait for paper to completely dry.
After measuring the paper dimensions, straighten the piece and start cutting the tape to cover around 0.25 to 0.5 inches of the paper edges. Reduce the amount of moisture on your paper by laying a towel or paper towel over the top of your newly stretched paper. First you soak the paper, then you stretch it.
How to stretch the paper:
This video shows my preferred method, stretching on the same stretcher bars used for canvas, and an alternate method for those who have difficulty. Stick the tape along all four edges of your paper. Fill a large sink or bath with water and submerge the paper, rolling or folding it as necessary, but avoiding creasing it. Using a utility sponge moisten the adhesive on the tape for the top edge of your paper.