If you are someone who is diving into Linux for the first time it can be a somewhat daunting task learning all the ins and outs of the operating system. We are all beginners at one point or another. The following is a list of tidbits and tips I have learned over my years working with Linux that will help you learn/maintain your Linux based operating system.
1.) If you can't find what you are looking for - ask. Odds are the Linux distribution you are trying has a community forum where you can ask a question, if you are looking for something distro-neutral LinuxQuestions.org is one of my personal favorites, or if you are looking for something a bit more "real time" #Linux over on irc.freenode.net is typically very helpful. Regardless of where you ask, please remember to ask smart questions.
2.) If something breaks, do not simply reinstall your operating system. It is worth the time to debug the issue and actually fix it. If something became messed up once, odds are it might mess up again and fixing something is typically much quicker than having to reinstall each and every time (once you know what you are doing).
3.) The following mantra describes what I think is the best way to learn the guts of your operating system "If it isn't broken, fix it until it is, find out what went wrong, and fix it" By this I mean tinker with what you can, change settings, add programs, remove programs, compile things from source, whatever it is you want to learn.
4.) If you are unsure what you want, then try as many different distributions as possible (they are free after all). Different distros use different default application sets, package managers, display managers, and many other things. Odds are you will find pieces of each distro you like and pieces you don't like. Once you have this figured out you can make an educated decision on which one is right for you.
5.) Now even though all those Linux distros are free downloads, burning hundreds of CDs/DVDs can become a costly endeavor. If your system is able to boot from a USB drive, I highly recommend picking up a 4+gig flash drive so you can use Unetbootin instead of discs.
6.) Linux is not Windows. If you are trying it with the expectation that it is a "Free version of Windows" you are going to be in for a world of frustration and disappointment. You should want to use Linux because it is a better operating system than Windows, not because it is cheaper.
7.) If you discover you love Linux and all this free software, that is great! Just do us all a favor and don't be a "Linux Zealot" As much as some of us would like it to be Linux is not the be all end all for all computer operating systems. It is not going to work for everyone. Forcing someone who does not want Linux to use it is only going to cause both of you a world of headaches. There is a right way and a wrong way to promote your operating system of choice.
8.) Finally, if you haven't already, it is time your become acquainted with the Linux Answer Machine. The reason for this is that rarely are you the first one to attempt whatever it is you are trying to do, finding someone's success (or failure) story can often save you hours of headache and hacking.
Hopefully you learned a thing or two! If you have your own tips you like to share with Linux noobies that I did not list here let me know by dropping a comment below.