Here's what I do. I just finished a lapghan for myself, and I had crocheted in black around each square. This is a personal thing, lots of people don't. Then I crocheted in black around the whole thing for a finished look. When crocheting around, you could crochet over the tied off ends. When going around the whole thing, I did two rows in single crochet, then two rows in double. I'm pleased with it.... used up some squares a friend had sent me a couple of years ago, and now when I use the lapghan, I think of her (smile).
I'll have to take a pic of the thing a post a link.
Shelagh