Bag Valve Mask
As absolutely essential skill. I strongly recommend a two hand technique for anyone who isn’t doing this multiple times a day. More info in this post.
Don’t think of this as one procedure. Break it down into micro-steps, and know how to trouble shoot each step. More info in this post.
Focus on tube delivery over a perfect view. Understand the different mechanics of hyperangulated blades. More info in this post.
A good general overview of preparation for RSI. More info in this post.