Here's how you gain lots of XP. Reply to questions quickly and get upvoted.
As long as you don't write total nonsense, it doesn't matter what quality your answers are, because people will upvote moderately good answers the same as very good answers. There are no double or triple upvotes.
On the other hand, it does help a lot to reply quickly, because many people will check out most questions only once, and will visit only very few questions again, the ones they have found interesting or relevant to them. Thus, your answer gets a chance to be seen by many people only if you answer fast, before other people visit the same question. The scale is a few hours during the American workday, when most monks visit the site, or up to two days during a weekend.
Further, if a question get multiple replies, they are by default displayed in increasing order of posting time, and the readers may get bored before reading all replies. Due to this, if you expect that a question is easy and will get multiple replies quickly, it may even be worth to cheat by creating your reply first, then filling it with most of the content later, so that it appears above other replies even if you can't write very fast. This is, of course, risky, because if monks see your unfinished reply they might downvote.
You can write questions or other root notes too, with good titles so that people check them out. I've just found that more difficult than writing answers.
Make your writeups easy to understand, not deeply meaningful, because the internet is like television, most of the readers have a short attention span and won't think deeply on the meaning of your nodes. (This doesn't mean you shouldn't post writeups that are well thought out and deep, it's just that they're not the easy way to gain XP.)
When you notice a question such that some older question or reply of yours may be relevant, post a reply linking to those older threads. This way, you direct readers to read and vote on older threads that they would otherwise never see, and get upvotes from them. Notice questions that occurr frequently in Seekers of Perl Wisdom, give an answer to one instance, and then in each following instance, give a link to all older questions asking the same. If you just gave the right answer to a repeating question, you'd get only one upvote. If you link to multiple older questions where you have given the right answer, you'll probably get multiple upvotes, regardless of whether you copy your answer.
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