Tips on moving off ponies?

Heya I am sad to say I have to retire my 14.1 pony due to a leg injury so he is going to his retirement home and I have technically outgrown him :( so we have found a new horsey who is 16.1 he is so nice very similar to my pony at the mo :D I was just wondering if anyone had any tips when moving off ponies onto horses. I am very tall and fit perfectly and we are getting my new horse vetted so please don't say he is to big cause he isn't :) thanks guys xxx