You all meet in a bar

You're the GM and you have a bunch of PCs with non-intersecting backstories first meet each other in a public place.

What do you do to make it so they would "party up" so to speak and go around doing stuff together?

The classic choice is the quest, offer them a lucrative job which will require them to work together, then just hope your players aren't non-roleplaying morons.

Not all characters will accept random job offers, especially dangerous ones. And of course players will take any excuse to hang out in-character but a better GM can tie it all in.

OP what about they all get kidnapped and as they escape whatever prison they're in, they befriend eachother and vow to get to the bottom of the mystery. Or something. Might be too rail-roady.

>Not all characters will accept random job offers, especially dangerous ones

It's at least partially the player's job to get their character interested in the story. Nobody enjoys a game grinding to a halt while the DM tries to work what the fuck is going to make John's monk stop talking about how all physical reward is ephemeral and accept the damn job so we can play.

Read Foodfight (Shadowrun module).

>And of course players will take any excuse to hang out in-character but a better GM can tie it all in.

Someone throws another man on the table the PCs are eating at. Their meal is ruined, their drinks spilled and their clothes completely fucked.

Turns out the guy that threw that man is a big, hulking thug belonging to a biker gang, who is now laughing at the PCs for how stupid they look with pasta, ravioli and beer all over them. They think it's really, really funny.

What do you do?

Give them a common enemy

...

To be honest, the best way to solve this problem is just to circumvent it. I find its usually a much better start to give (or, prefferably, invent with your players) a starting scenario which roughly defines their relationships e.g. "You are a band of mercenaries, and have just recieved a strange letter..." Its best to do this before characters get put together, for obvious reasons.

It means you don't have to faff around with taverns as the PCs now have at least a rudimentary link to each other, and that you can immediately throw a couple of appropriate hooks or encounters their way to get the ball rolling. If you can pull it off, you can even start them already on some kind of job.

Don't allow them to have non-intersecting backstories. Every motherfucker should have already met at least one other motherfucker, preferably two.

Yeah yeah but sometimes it is fun to do it this way instead. Meeting for the very first time, roleplaying learning about someone new. It's fun. A different kind of fun.

All of them are arrested in this public place when the [OFFICIAL GOON SQUAD] raids the joint.

Now they're in the slammer together. What do?

Entwining character backstories to allow for a more realistic teaming up should be part of basic group character creation.

Working characters goals should also be party of coming up with ideas and hooks for the campaign as a whole.

Woah Shaggy is a fucking badass

I typically describe every player seperately on each player's turn, with a slant towards what I know abou each character's perspective so far (this actually helps people who don't get into roleplaying as easily get a clearer picture of their own character), along with a little humor to start the game off. Essentially, I try and give the players a reason to talk to eachother before shot hits the fan.

If they don't (an they're not obliged to), I create a little event that will get them all involved. No really related to the "main quest", just something that'll get them roleplaying. It's a bar, shit happens, have fun with it.

Though once, that "mini event turned into the "main quest". Basically, one player hit on a chick who just so happens was someone there's girl, confrontation happened, other players got his back (they'd talked for a while, it wasn't just "oh we're players gotta stick together XD"). One thing lead to another, I tried to be lenient, but eventually the only way that I could maintain the illusion of consequence was to send them to prison. And that became the entire game. One player kep trying to figure out a way to escape, one tried to become the kingpin of the prison, one had this feud with a goblin gang, and obviously a bunch of little stuff. What started out as a more or less typical campaign became an extremely memorable one, all because I let the "you all meet in a bar" scene be more than just a narrative launchpad.

Tldr let the bar be a fucking bar

If I remember correctly he was possessed by a demon in this scene

That woman is looking at the other woman's breasts. She has to look up to connect her gaze to anything above shoulder-level, its limited by the edge of her helmet's visor, so that she can't see any of the pink shaded area. Her friend can see all of her immediately and easily.

that must be troublesome.

That's easy, just have the most educated person in the party engage him in a philosophical debate.

>this money you offer means nothing to me
Ah, but you focus to much on the money. You are so focused on avoiding material greed the avoidance itself has possessed you.
>Hm?
Consider a tree. It's leaves fall not because the tree is after the reward, but because they must. How else would the grub worm live if not for those falling leaves? And when the grub eats, the soil is enriched, and all is better. Accept this quest not because you desire the money, but to put the world jut a little more in balance.
>you have convinced me, I shall join you

It's called ropeplaying you dip. It's fun, you should try it.

Womanlets, when will they learn?

>ropeplaying

Doing sorta this for a shadowrun campaign, it's even more interesting because each player was arrested by KE in their homes, so in addition to being thrown in jail together and meeting a new lawyer contact, they also have to deal with KE knowing where they live.

>you have a bunch of PCs with non-interesting backstories
yep, that sounds about right.

Honestly, if your players aren't all contrarian chucklefucks, they'll group up together even if you don't give them a hook at all, because they all wanted to play a tabletop game together. The hook helps, but I've had great games that just start with "you guys are all in a tavern and you're going to form an adventuring party."

I just don't have this problem. My campaigns start out outlining some sort of goal or event, and the only requirement is that in your character's backstory, you give him some reason to care.
>An ancient evil has awoken, the church seeks volunteers to slay it
>The archmage has decided to take on a disciple, but he must prove himself worthy first