My most recommended look with over the knee boots is matching with mini skirt or t - shirt dress which stops at upper thigh. (myeternalsymphony.com)
Keep hips square and place a block underneath right upper thigh. (blog.paleohacks.com)
Bring the side of your hips together and then raise your leg as they raise the opposite leg and guide them onto your inner upper thighs. (fitbodyhq.com)