Glad you asked...
It starts with understanding symbols and language of electronics. It is not difficult once you under stand the symbols and what they represent. You can find more information here: http://library.thinkquest.org/10784/circ...
Then again, this answer might help you...
If your goal is to read a electrical drawing you need to be learned in electricity and circuit theory. The symbols used are internationally universal. Once you are learned on that it will be easy. You can get any of these books from your library.

