I would like to do a collab with someone but I don't know how to do one. Does anyone else know? Also, if you do collab how do you share it?
Thanks,
Lovetosingloads

A collaboration is where a group of users work together to make a project. This is often done by using remixing to add onto each other's work or by making a bunch of separate projects to be compiled into one whole game/animation/ect later. If you know thew person you want to collab with in real life, you can make a shared account, but be careful as the scratch team could ban you if they are unsure that you know each other well enough.
Most people do collaborations in the collaborations forum. You just make a thread there explaining what you'd like to make and what kind of people you need and hope for the best. Most people will set a specific criteria for what kind of people they want or just ask to see a user's previous work to make sure that they're good enough for the collab.
You could also ask a scratcher that you're friendly with if they want to collab with you on something.

Also if you want people to add changes to the project, you can try the “Remix” tool.