Well, my first tip would be to find a good teacher and do what he or she says.
If you're a "newbie," it may be too early for many real tips, but I guess that I would also suggest paying very close attention to your technique. Ask your teacher if you're ready to learn scales, and if not, then ask for some other technical exercises. I would spend probably between a quarter and a third of your practice time doing technical exercises -- use them as warm-ups. Don't just rush through them; take your time, start slowly, and make sure you're using correct form! (These exercises are pretty much pointless if you're not doing them correctly -- after all "Practice doesn't make perfect; perfect practice makes perfect.")
My last (and most important) bit of advice is to have fun! Play some things that you like, even if your teacher assigns you some things you don't. You don't wanna get burned out!
I hope that helped some. Feel free to post any more questions you have; I like talking about music, if you couldn't tell. 
-Nick
PS -- I just remembered one more thing: I found that it helps your practicing if you can have as much privacy as possible. If you are aware of the fact that anyone else can hear you, deep down, you'll try to "perform" for them and not "practice."
