Step 1: Pick a program.
Step 2: Scribble.
Step 3: Examine the Giant's work.
Step 4: Scribble some more.
Step 5: Give up, and look for one of the How To guides on here.
Step 6: Scribble some more, but better this time.
Step 7: Practice.
Step 8: Take on some requests, but just for practice.
Step 9: Tentatively take on a request for real. Get shot down.
Step 10: Practice.
Step 11: Tentatively take on another request for real. Get asked for changes. Panic.
Step 12: Get a request approximately right.
Step 13+: Take on more requests. Get better. Rock on.