I personally prefer a continuous string of rollovers with muscle up negatives rather than the jumping muscle up approach, but either is fine; the most important part is the muscle up negative. For this part, check your speed by focusing on the speed that your elbows come down through the transition. Ensure that you are moving them slowly and with control throughout the movement. In addition to high pull ups (chest to bar), I also suggest deep dips (chest to bar). I personally preferred working false grip pull ups to explosive regular pull ups, however I was aiming for false grip muscle ups from the get go. Either way, at the top of the pull up try to focus on “rolling” your shoulders over your hands. Also, contracting a tight L hold with your legs at the top of the pull up is ideal. To that end, it wouldn’t be a bad idea to work on hanging leg raises and/or L sits as well.
And for the sake of completeness, I recommend also working on pistol squats, handstand push ups, and bridging exercises.