Same here, mostly I just make my block (or the pattern) up as I go along.

I try to do a test block, especially if the quilt is a little complicated, but not a complete mock up, thats too much work

I do a sample block. I want to make sure I can make it and that I like it once it is actually made before I cut up all my fabric.

Sometimes I do make a test block especially if I'm not sure the pattern is correct.

I usually don't. If I don't like it when done, I can give it to someone~

Only if it's a technique that I don't do too often (paper piecing) or if it's just something that I'm dreaming up and I want to see how the colors work. Even if it's just scraps and not the actual fabric I'll be using just to see if I like the layout.