Remember that engineering is work, and no document will substitute for your own thinking, learning and experimentation.
- Play with something.
- Read the documentation on it.
- Play with it some more.
- Read documentation again.
- Play with it some more.
- Read documentation again.
- Play with it some more.
- Read documentation again.
- Get the idea?
The idea is that your mind can only accept so much 'new data' in a single session. Playing with something doesn't introduce very much new data, but it does transform data in your head from the 'new' category to the 'familiar' category. Reading documentation doesn't make anything 'familiar', but it refills your 'new' hopper.
Most people, if they even read documentation in the first place, never return to it. They come to a certain minimum level of proficiency and stop. However, modern operating systems, programming languages, and networks simply cannot be learned in a single session. You have to work through the two-step learning cycle many times to master it.