If you want to let's say learn, the Cardschat course that @Andyreas
mentioned is very good, you will learn quickly with practice of course.
The only books I have read are those by Doyle Brundson, Super system 1 and 2 and the wisdom of a champion are the ones I have read and they are very good.
As for my preferences, it is really watching a lot of poker online
, especially MTT live and online.
I analyze plays, I see strategies, I really like doing it a lot.
My regards, brother