 When you need a quick custom size board for prototyping, some single-sided perforated board can be cut with scissors, which is nice. But it's surprisingly easy to resize thicker and double-sided boards as well. First, measure and mark the desired size, then score the board with a ruler and utility knife along the perforated holes. It doesn't have to be too deep, just a couple firm passes should do. If you're removing a substantial piece, you can simply press the board against a table at an angle, and the one piece will become two. For thinner strips, you can place the board in a table vise and bend along the seam. Either way, the process is literally a snap.