Simple, Get ammo if needed from entities, go to options tab in teh Q menu, then click create and left click
Have someone press E on it, done

What if you want to collar an NPC? How does that work?

That's not simple, it's confusing

So Firstly you will need to hold down your Q Key.Once it has been held down, the spawn menu should appear, drag your mouse to the where your tools would usually be but go up and select options.Then There Should be an option to create a collar.Create the collar on your friend and make them press the E key on it, just tab it.They should now be wearing the collar.

still didnt work