Last I heard, you just get paid by the post or comment. Earnings. When paid, vary between 25¢ and 50¢, although there are occasional bonuses I've heard of.
Limbaugh callers, however, hit the jackpot at $45 per call. But they earn it.
First, they have to be aware of American politics. This wouldn't be a problem except that he can't really advertise in the US. To get around that, his company advertises in Canada. If there is a twinge of Canadian accent, the person is from a border state like Minnesota or Michigan's Upper Peninsula.
For Internet trolling, contact the party leader in your area. While they may not know who to contact directly, that would at least put you on the right track. If you're new to the party, you'll be out of luck. Still, on some areas, if you're limited on employability and your dad is a strong party member, that helps.
Once hired, Although you're actually a 1099 private contractor, you will be given an amount of posts to produce and you will need to check your email several times daily to make sure you have the proper "trigger" talking points. Look through the latest memes and you'll see the same talking points over and over.
While I can't prove it, you don't need to have facts behind your meme, comments, or replies. I just commented on a meme that hasn't even been featured yet, but was shared on Facebook. Lord only knows where the guy shares the all to, but by the time it's featured, it can have a lot of views, even upvotes if the people that follow the link are members.
Hope this helps