Yeah your stirrups are WAY too short.. and your saddle it too far forward. Have you been working with a riding instructor before this?
Your arms look stiff.. which is causing your horse to not stretch out and find rhythm at the walk. Try loosening them up and follow the horse's movement :)
You're moving too much of your upper body with each step the horse takes... quieten your top half and allow your hips to move. I guarantee they're stuck due to the saddle.. it's not doing your positioning any justice.
I don't see your horse loose enough for you to sit trot on right away.. I'd always try to post before I attempted sitting trot, merely to prepare my horse to have a nice soft working back.
"Strength is the ability to use a muscle without tension"
Last edited by Skyseternalangel; 02-25-2013 at 07:54 PM.