Writing is at once the easiest and the most difficult thing in the world. Unlike, say, drawing, anyone can sit down, throw something together, and no matter what they actually wrote, it
looks just as good as anyone else's writing.
The best advice I can give you is to write in batches. Sit down one day and just pump out as many jokes as you can. Edit as you go, sure, but just focus on quantity, not creating finished work.
Then let it sit for a day or two. Not so long that you forget what inspired the joke, but not so short that you're still caught up in the excitement of thinking of it.
Then tweak it. Edit it. Ask yourself, "what would make this funnier?" and think about why. Ask what makes what you wrote funny in the first place. Consider that maybe you've got a great idea, but if you found a way to be more surprising or create more incongruity, it would be better.
Here's an example of something I wrote then tweaked.
DRAFT 1:
Panel 1]
Character A: Is it wrong that I think my girlfriend is prettier when she's all wet?
Panel2]
Character B: I wouldn't necessarily say "wrong."
Panel 3]
Character A: What if I only want to have sex with her in the shower?
It's not awful, but it's not very good either. The joke is kind of telegraphed and there isn't a ton of incongruity or surprise. After a while, I came up with this.
DRAFT 2:
Panel 1]
Character A: Is it wrong that I think my girlfriend is prettier when she cries?
Panel2]
Character B: I wouldn't necessarily say "wrong."
Panel 3]
Character A: Is it wrong to pee on my girlfriend to make her prettier?
Will it go down in history as the greatest comic ever? No. Is it better than the first draft? I think so.
So much of writing jokes is leading the audience in one direction--setting up their expectation for one, very specific idea, and then giving them something else at the very last moment.
If it helps, think of it like throwing a curveball in baseball. The idea is that the hitter thinks the pitch is going right down the middle...and then suddenly, they're swinging for the fences but the ball isn't there any more. It's somewhere else.
Writing in specifics helps too. Generally speaking, the more specific you are, the better. A punchline about Pizza Hut will land better than a joke about "cheap food." Similarly, a punchline about the fact that they currently offer a special meal box that includes a pizza, cheesy sticks, and cinnamon sticks--which is basically just a $15 box of bread will land better than a joke about "Pizza Hut."
And sometimes you just have to be okay with the fact that sometimes a concept is funny, but it's not really a joke. You obviously want to work to write a complete joke, but sometimes you just make a comic and it's just a funny idea. That can be okay too.
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I write at cn-comics!
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