Dos;
• Follow the rules,
• Do more or reading than writing,
• Join discussions,
• Find what interests you,
• Keep reading,
• Slowly acquire more knowledge as you get good at the basics,
• Do more reading.

Donts;
• Do not plagiarize,
• Do not spam,
• Do not spread malware.

The forum's metric is activity and merits which gives you your rank, with your merit being the most important of the two.
Your personal metric which is by far more important is how much you're learning and how close you're getting to your goal of being on the forum.