The trick is to not try to lift the bike onto the stand! (That will really pull your back out!) Make sure the rear shocks have the right amount of air. Low on air, bike sits lower, twice as hard to get up on center stand. Detdrbuzzard is right...be sure both feet of the stand are touching before trying to put it up.
On mine, I put down the center stand with both feet touching, press my foot down on the stand and hold down for a momemt, pull up slightly on the seat while pulluing back on the bike and pressing down on the stand at the same time in one smooth movement. Gotta watch sometimes cause the bike gets moving real fast onto the stand and rocks abit!