- 1). Wet a sponge and wring it out slightly. You want it to be wet enough to get the canvas wet, but not so wet that the canvas becomes drenched.
- 2). Lay the painting so the paint side is down. Rub the sponge along the wrinkled areas of the painting. When canvas becomes wet, it shrinks, which will help get rid of the wrinkles.
- 3). Tack the painting painted side out onto the piece of plywood. Slowly stretch out each edge of the painting, tacking it to its new position. Stretching the canvas eliminates the wrinkles.
- 4). Allow the painting to dry before removing it from the plywood. Mount and frame it as soon as possible to prevent the painting from wrinkling again.
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