This comes up again and again in my classes. Students want to tape off a shape and make a nice, crisp hard edge. Too often after they've taped the shape off, painted it and pulled up the tape, they have a messy edge where the paint has crept under the tape.

Here's the trick to making a perfect, clean hard edged line or shape every time.

1. Use blue painter's tape and tape off your shape or line, burnish lightly with your thumb.
2. Paint over the taped edge with clear polymer medium or matte medium.
3. Let dry!
4. Paint back over the taped edge with your paint.
5. Let dry!
6. Peel up the tape and voila! you will have a nice clean edge.

The polymer medium acts as a seal to prevent the paint from creeping under the tape. No more fuzzy lines or shapes! Be patient and let the polymer dry before you paint on it and let the paint dry before you peel up the tape and you will have perfect shapes and lines every time.