FWIW, every bike I've owned has been much easier to get on the centerstand using the following procedure:
1) Lower the sidestand and dismount the bike on the left side.
2) With the bike on its sidestand, grasp the left handlebar with your left hand, and with your right hand, grasp any convenient handhold behind the seat.
3) With your RIGHT foot, lower the centerstand until the left-side tang is touching the ground.
4) Tip the bike away from you until both tangs of the centerstand are touching the ground.
5) Stand up on the centerstand with your right foot (your entire weight), and at the same time, pull upwards with both hands
6) Note: Standing on the centerstand gives the most leverage; pulling up (or possibly rearward, but usually straight up) will add to it, but I've found that the standing motion (all of your weight on your right foot) is what makes putting the bike on the centerstand a snap.
Cheers