I think that one useful thing would be for beginners asking questions to make their threads self-moderating. They could then delete the spam posts,
Agree with it, but problem is most of newbie don't know about self moderated thread (IMO). I think I should make thread about it and explain benifits of selfmoderatrd thread to avoid spam. Or if there is others thread than it should be up.
Another really useful trick is to close the thread once you question has been answered. This will avoid it becoming a spamfest as the spammers keep repeating the previously posted answers.
Exactly, I already mentioned it on avoid spam row. Thread could be locked after got appropriate answer in order to avoid spam. Usually people's just make similar answer if thread isn't locked. So it will be most helpful.
If you have any question search before you make post and you should lock thread after got answers. So other people's will not able to spam on your thread. Don't reply if you don't have proper knowledge according to main thread.