How to get familiar with a system

[by]

Hi,

I really want to get familiar with an operating system, and i am using 
FreeBSD 10 RELEASE on an i386 machine now, but the problem is how to 
start, or i would say, what methods can be used to uncover the secret of 
an operating system?

Cause i have install the source code on my machine, i have tried to hack 
the basic utilities one by one, like echo, ls, cat, etc. But i find i 
work too slow, and i can not find the exciting experience i have got 
before for resolving a problem. I know people can not dive into every 
detail, just one deeply dig is okay. But i find i have no motion now, 
may be i need a project : )
And i know my skill is too poor to be a system programmer, at least i 
hope i can be one : ) So anyone who already has familiar with an 
operating system could share some ideas?
Everyone must has a beginning, and everyone has everyone's own ideas to 
hack, but as a new comer, i still hope to get some ideas.
I know this is not a very specific questions, so i have not search the 
mailing list to find some related answers, or i just want to interact 
with hackers rather than the history papers as a question like this, i 
hope this is not too rude : )
Maybe because of the environment i live, i find it is not as easy as you 
to get so many chances to practice, or just because of my lack of 
courage. Maybe i should start up a company to push myself to work on 
this, or i just need a related job and do my own hacks. I do not know 
how to do.
Maybe i need a plan, actually, i have just planed for some book reading 
everyday, i would say, there are three books, which are C related, UNIX 
related, and of course FreeBSD related. I read these three books 
everyday but just a little, i know my poor English and poor ability for 
solving problems make my slow reading, and i know i make those three 
books as dictionaries, and i think they are, and i know after i finish 
the slow reading, when i get some problems in the future, i can get 
benefits from this slow reading, and find related solving ways quickly 
from these three books. But i know hackers should do some real things 
not just for theories related. Maybe i really need to involve myself 
into a small, real, project, any suggestion?
Well, i feel it is very stupid for asking questions like this, but i 
know i really need this.
Actually the final problem is how to recognize this world, from a small, 
simple point, or from the universe view?
: )

- by