As you are already using the site to search for answers, I suggest using the opportunity to look for duplicates.
Track them down
Often a Google search turns up essentially the same question asked in different ways (or in nearly the exact same way). Example: high-resolution timing on Windows (asked over, and over and again). Decide on the canonical question (usually the oldest).
Add comments to the other questions suggesting they are duplicates of this canonical question (I am not sure about the official policy for users under 3,000 reputation points using the flagging system for closing questions, but if it is all right they can be flagged as well). The comments will very much help in the future when users decide on casting close votes or not.
Some users don't like their questions being closed, so a little courtesy may be in order. Therefore I will not suggest the exact phrasing of those comments; find your own style that works best for you. A starting point may be the (neutral) text that is usually automatically inserted when the first user with closing rights votes to close a question*1:
Possible duplicate of XYZ.
Make it awesome
Now turn the attention to the canonical question:
Suggest (comprehensive) edits to the question
Make the best answer (often the accepted or highest-voted) the whole Internet's definite answer for this question.
Make the answer comprehensive - often an existing answer may be vague, missing details, be missing (working) sample code, only be a pointer in the right direction (not really operational without a lot of effort on the reader), etc. Synthesise all the answers, including from the duplicates, into the definitive answer.
Make the answer easy to understand: add annotated screenshots, avoid the wall of text, pay attention to formatting (but don't overdo it), etc.
Either make the change by:
- Suggesting an edit to the answer, or (as the change may be too drastic),
- Provide your own answer
While the answer should be comprehensive, it should also be succinct. You may consider using the inverted pyramid.
Getting reputation points should not be your main concern, but you will get it immediately from suggested edits and for the longer term from your own answers (there is little attention on old questions, but Stack Overflow users, who find the great answers through Google Search, will often upvote).
*1 Source is (replace with the real title and the real URL):
Possible duplicate of [*XYZ*](http://stackoverflow.com/questions/ABC).