What can I do to give back to the forum? The forum gave a lot of sound advice, answered my question, enriched my knowledge, and supported me in my queries. What can I do to give back to the forum?
You can edit low quality posts to improve them.
Once you've gained enough reputation you'll be able to review posts from other users, to help out with the moderation of the site.
I think one of the best things to do is be welcoming and understanding to users who are even newer than yourself; to help them by explaining how best to use the site, how to stay on-topic, and so on.
An even simpler thing is just to make sure you vote up questions and answers that you've found helpful!