1. You clean the surface area with alcohol to allow the adhesive to work
2. You do it on a warm enough surface
3. You give it AT LEAST 24 hours for the adhesive to cure (which is where most people seem to make the mistake)
If you can create a TEATHER (they make ones that fit into a second adhesive pad) that will keep you from losing it should the first one fail.
Make sure you don't put it somewhere that you scrape it off if you lean over too much (see Pashnit); if you really want to see some mounting Ideas, I think he's tried them all)...
pay the $30 and grab a suction unit. you can mount that bad boy almost anywhere on the bike and not worry about it coming off on high speed runs. this is a quick triple digit blast last night mounted on the windscreen out front. little shaky because i slapped it on the lower part of the screen.