This is the cheat sheet that I used to get started: http://home.uchicago.edu/~gan/file/vim.pdf

Learn the basics first:

1. Basic movement (h l k j)

2. Insertion mode (i), deletion (x), selections/visual Mode (v), copying/yank (y), pasting/put (p), and exit insertion mode (esc)

Once you learn those the rest is pretty easy to pick up.

I should warn you though, once you get used to the key commands it's hard to go back to another editor.