As the resident Life of the Party--an official title I take very seriously, like World's Best Uncle or Bank of America Customer 4,576,291--I feel it is my duty to be fun and funny. And then I thought about it. I already exposed how I put together these job lists for you so in the spirit of revealing my entire operation, here is how I write humor.
First, be funny. You cannot write humor without being funny. I would suggest that you spend some time being funny, like perhaps making observations that seem obvious but turn them on their ear slightly so people see them differently. Or perhaps you ought to take two things that aren't alike but then make a comparison between the two of them so that people laugh. People generally laugh when you create tension or confusion and then explain it. Sometimes they also laugh at people like Dane Cook. That is something I cannot explain.
Second, write something. So that would mean forgetting that it's your day to write a humor article for a website that you happen to work for--say, for example, a freelance writing site--and then putting together some sort of hastily written material so that you don't fail to meet your commitment. I would recommend not sitting down and researching anything, as that would make you prepared and your jokes more clever. Instead, just put down any old thing and then make a wry observation. I find that helps.
Third, combine the two.
Fourth, find people that want you to be funny for a living. I would hit up clients like comedy clubs, The Daily Show with Jon Stewart, and laugh factories. There are also content mills that specifically deal with comedy that I just made up and didn't research, so you should try to find those too. You can also easily get a job writing for a comedian by being funnier than them and writing better jokes, then mailing those jokes to them and sending a SASE for their payment. I have earned several restraining orders this way.
Fifth, drink your earnings away. Be smart about this. I would recommend bargain shopping for alcohol, as you are probably going to combine cheap bourbon or vodka with Sprite or Fanta anyway. My favorite alcohols come in plastic bottles and are simply marked Alcohol XXX. Brands are only going to fool you into treating your liver with any modicum of respect. Be sure to drink alone. If you get any joke ideas, write them down. That way your friends--the ones who tell you to get a real job--can't steal them.
Sixth, go find a real job.
I wish you great success as I have had as a humorian. I bid you a fond farewell.
Disclaimer: following any of the above advice would make you no money or friends, but perhaps you'd meet a cute girl at Alcoholics Anonymous. But then you'd probably go and mess that up too.