Considering an antistatic strap costs about $5, "better safe than sorry" won't cost you much. That being said, I had a strap, and always forgot to plug it back in every time I went to get a drink of water. A lot of people don't really seem to mind and just suggest touching metal bits. As was said, avoid walking over carpet and you'll probably be ok for the most part. If your board is something like the asus sabertooth then maybe try to touch the thermal armor/metal backplate more than the board itself. Don't build in a lightning storm. ...