I don't use the hook - I've had a bad experience with the stand actually lifting off the hook when I went to level it, so instead I use the offset bracket (you can't use both).
I just use the top most versa button, tighten the strap down, and step out onto the platform. flip the seat down, kneel on it, and use my toe to pull up the edge of the platform and collapse the stand - this will cause the whole stand to drop down, and lock the offset bracket/strap securely to the tree. Then I just push the platform back level, which acts like a lever and locks the stand in place.
It's super secure, and won't budge an inch - infact if you don't tighten up the single strap and do the above, you can generate a TON of leverage on the stand's frame - almost to the point of bending it, so be careful!