If you want an edge to paint against, use those those little 'sticks' or canvas keys that come with a canvas to tighten it up. Put one next to the area you are brushing or knifing in to act as a fence or barrier. Just hold it in place while you work, and pick it straight up off the canvas when you are done.
Tip from: Starrpoint
Submit Your Own Painting Tip:
Got a great painting tip to share with other artists? Use this easy form to send it in: Submit a Painting Tip Form.
More Painting Tips:

