<p>To clarify (though all the parts of this information is here in various places):</p>

<ul>
<li><p>On the main site, you can normally answer a question with 1 reputation. </p></li>
<li><p>Here on meta you need 5 reputation to answer</p></li>
<li><p>You need 50 reputation to comment in either location.</p></li>
</ul>

<p>$\,$</p>

<p><strong>To gain reputation quickly</strong>:</p>

<ul>
<li><p>answer questions on the main site. Good answers will generally get upvoted; this is the fast route to reputation. An average answer should typically get you about 30 points or so (but even an experienced answerer with a higher average will get 0 points sometimes). [However, it might take a while to figure out the kinds of answers that tend to be worth more - my average was below the site average for a long while. Other people may be faster on the uptake than I was.]</p>

<p>There are many unanswered questions, so there's plenty of opportunity for points. An even slightly determined person can get 50 points in a session.</p></li>
<li><p>ask good questions on the main site. This is often a little slower, but a very good question gets a lot of attention, and one that attracts good answers gets a lot more. You don't need to be able to answer questions to garner a lot of reputation.</p></li>
<li><p>if you have good reputation on other SE sites and the site knows they belong to the same person (i.e. you register the accounts from the same email), you should get a bonus (this one doesn't look like it applies to you but may apply to other people who read this question).</p></li>
</ul>

<p>There's a list of sources of reputation in the <a href="https://stats.stackexchange.com/help/whats-reputation">help</a> (I know you already found this though - again, I am putting it here in an answer for later readers).</p>
