I can tell you what I did, whether it will help you or not is questionable
When my kids were coming 2yo I worked with them very little. Just started getting the "get ready to get on" stuff like standing still while I jumped up and down next to them. Ground tyeing, tying hard and just general desensitizing and giving to pressure exercises. Since they are a gaited breed and its recommended to wait till at least 3yo I figured I'd let them just be horses for as long as possible.
I know you read I got on them today and it was so much easier having gone through all the "get ready to get on" stuff for so long. I can already get them to move out and move left/right stop and that was in only 10 min. They just already know all that stuff.
I talked to a trainer friend of mine today (the one that's suppose to be helping me) She made the comment that the filly's have already gone through everything that they would be taught at a trainers to green break them. Everything I've been doing since the day they were born is what some are expected to learn in 90 days.
I think they have it down