1. Making a joke character
When I was younger and doing pretty much all of my roleplaying at a table, I had a friend whom I'll call Mark for the purpose of this column. Mark was a bit less into the whole idea of playing a roleplaying game as something with equal parts humor and seriousness, and as a result, his characters usually tended to not mesh with the rest of the world. As an example, I remember a dark fantasy campaign during which the party consisted of a half-vampire nobleman, a mage with an increasingly dim view of objective reality, a prince with a cursed blade... and a psychic clown.
No, not in the sense of a thinly veiled copy of Pennywise -- just a psychic clown. I think he was also a male escort; time has dimmed the memories.
The problem is that by creating a character good only for a laugh (such as "how did the clown get in there?"), you create a character who also destroys any attempts at serious development just by his presence. You can't take the character seriously even if he's acting serious at a given moment. Heck, it's hard to even take the world around you seriously when it's just being mocked by someone's presence.
You can make a character who's meant to be funnier compared to the rest of the group. (To continue giving Mark's character a hard time, I wouldn't be telling this story if his character had been a world-weary psychic wearing a ragged jester's costume with a penchant for cynical jokes and dry humor.) But creating someone who has no other purpose than being silly results in a character that's uninteresting at best and actively disruptive at worst. Make your character fit inside a serious world, even if he doesn't always take the world seriously.
2. Being relentless
A little bit of comedy can go a long way. And a little too much comedy can go way, way too far. I'm not talking about jokes that wind up offending people by content; I'm talking about jokes that offend people because they don't stop.
This is one of the problems that joke characters have, but even otherwise-fine characters can wind up succumbing to this pitfall when the player gets really sold on the idea of making jokes. Suddenly, every scene is an excuse to cram as many bits of witty dialogue in as humanly possible, with any hints of actual drama buried under scads of snarky asides. Maybe the jokes are good, and maybe they're not, but they lie so thick upon the ground that you can have no respite from them either way.
Of course, this is just as bad as having nonstop drama or nonstop romance or nonstop anything. No matter how much you might like eggnog, having it every day starts to get cloying, not to mention the fact that you'll get really fat. Having too much humor won't make you fat, but it will start to stick in your throat. Don't overdo it.
3. Relying on overused jokes
For all that the internet does well, such as paying me, it does have a tendency to find something mildly amusing and pound it into the ground. MMO communities are particularly bad about this, with memes ascending to the status of near-perpetual mention. However amusing it might have been at first (read: not very), at this point the "arrow to the knee" gag is long past the point of even producing a smirk.
Roleplaying jokes don't usually involve outright parroting of memes, but they can still get overused. The most common ones are jokes that have long since become old hat -- metahumor about being in an unreal world, for instance. But there are also jokes that get made once, then made again, and then repeated over and over within your circle of roleplayers. Maybe Val's character once ran from the sight of a bug, and so ever since then people have just not shut up about how Val's character is afraid of bugs.
This is problematic for several reasons. First, Val would probably like to explore some non-bug related aspects of her characters, but as soon as she steps onto the scene, out come the spider vanity pets. Second, repeating an existing joke is never as funny as coming up with something new. And third, anyone new coming to the group is going to have no idea why people are forcing laughter at this -- he'll probably walk away and just not come back.
But how I make good jokes?
Well, that's a topic for another week. This week, I'm just going to sign off by saying that you can mail praise to firstname.lastname@example.org, leave various other comments in the comment field below, and mail animosity to the Tips line like everyone else does. Next week, rather than follow up this column, I'm going to go back to semi-current events and talk about handling your character versus a major story in progress.
Every Friday, Eliot Lefebvre fills a column up with excellent advice on investing money, writing award-winning novels, and being elected to public office. Then he removes all of that, and you're left with Storyboard, which focuses on roleplaying in MMOs. It won't help you get elected, but it will help you pretend you did. And to answer the alt text, timing.