Replying to Park Skiing Progression!

Today was the first day up of the year for me. I am trying to get in to park skiing this year, but don't really know where to start. Today I learn a basic 90 degre grind on a fat box, and after a few more tries I was doing 180s out. There are so many other features to learn how to grind on. Skinny boxes, rails, and the big metal "tube" things that I don't know what their called. Anyways what I really want to know, is what should I learn in a sequence of easiest features/tricks to hardest features/ tricks to ensure good progression. so a list of the different types of features I should be learning to grind first,second, third, etc would be great! Thanks.