Make notes after reading a book - you can't remember everything

It’s a typical situation which every person knows: You look on your workspace and have a bunch of new books there. You ordered them because some great guys lay their hands in the fire that you need this wisdom. Of course you have to do a stressful job and don’t have time to read all the things but you still must learn new things in order to develop new skills. What should you do? I just started reading as much as I can.