For best results, the bike needs to be upright, with you on it, and a second person adjusting the bars for you to get them in the best position (which may or may not be good enough) - and once in that position, tighten the bolts just enough to hold them in place, for you to dismount, secure the bike, and complete tightening.
There has been ample discussion on this site, including this thread. Go back and re-read it carefully. Armed with this knowledge, the job is one of the more straightforward on the Rocket.