Like allenb1983 says, there's a lot of information out listed on Google on this topic.

There are 2 areas that are important for system administrators: skills and qualities. Skills are pretty self explanitory but qualities are the things good system administrators possess as part of their "being".

I'll give you some insight into the qualities people look for in system administrators (in order of importance IMO)...

* Logical thinking
* Analytical: good at analyzing something
* Problem solver: good at problem solving
* Quick learner: must be able to pick new things up quickly
* Adaptable/flexible: can adapt to any situation
* Engineering mentality
* Communication: many sys admins are not too good at communicating...if you are it will help you stand out of the pack

This was just off the top of my head thoughts on this, do some research on career sites that offer info about sys admin jobs. I would also read the job postings to see what they are looking for.

Good luck.