I leave a photocopy of the topo map with my intended route highlighted. I also mark the perimeter of the area I'll be in with "will not cross these boundaries" hash marks. It's easy to set finite boundaries in Colorado - usually I'm hiking in some mountain drainage and it's easy to keep yourself from "accidently" crossing these towering ridges on either side of you. They make great funnels to keep you within a well defined area, even if you venture off-trail. It's easy enough to get yourself temporarily lost anywhere, but not to the extreme that you inadvertantly scale a 14,000 foot peak and wander down the other side of it.