I use whatever gear is necessary to keep the RPMs between 2500-3000 going uphill. Drop OD first, then downshift as necessary. If the downgrade is similar, use the lowest gear that you ended up in when climbing the other side. As Bob and Donna said, stab the brakes hard for a few seconds and release them, don't ride them.
Steve, Mary & Buddy our 2-year-old Chihuahua mix
1995 36' HR Endeavor, 460 w/Banks, 2005 PT Cruiser
Fulltimers originally from Michigan, hanging out in Oregon for a spell.