and of course, check out some ready made routines (choose only those who are well commented) and get some ideas. It will also help alot.
I would not really say that so. If the routine is not for training purposes, it might get really hard to understand.
You only need to understand the philosophy and all others will come to you. Practice practice practice.
Start with easy routines like how to light a led or something like that.
Then continue with how to blink a led etc etc etc.