Quote:
should I focus more on a tight style or aggresive?
Dude, please don't take this the wrong way, but this is exactly the type of question a TRUE beginner would ask. In your OP, you said you didn't consider yourself a beginner. It's one thing to be confident but it's another to be foolish. That's not to say you aren't asking good questions, because you are, just make sure you're open to criticism afterwards.
Getting back to your question, you shouldn't focus on any one style and stick to it. You must be able to adapt to the table environment and exploit any weaknesses you might find. In general terms, this means play tight vs the weak and vice versa, but ALWAYS be aggressive.
Go read Winning Low Limit Hold'em by Lee Jones. After you can comprehend and put it into practice, then move on to the more in-depth books like HOH and NLHT&P.