Recently a physics update made some of these not possible. I will gather all possible results that can be made. Simplest at least, to update this page.
In braains.io, you have 100 seconds to create a barricade using what materials you have around you: chairs, tables, even a truck. You can do this solo or with other people. When you create a base, remember barricades can and will be moved by zombies, so make something that's braced against a wall and go for sturdiness if you can. A popular strategy is simply using players as a barricade, topped with a box or such so the zombies can't eat your braains.
If you're not sure where to go, follow players with high scores and/or players with baseball bats, potato guns, etc. If you do this, remember to keep up with them, or you might get blocked out of a good spot. You can also just go to popular spots like the garage with the yellow car, the kitchen in the bottom-left section of the bottom house, or the separate building on the right side of the map.
Another strategy is to just run or hide. You can hide in bushes, and then run when you're found out. To effectively run, it's best to have a higher score (which affects your speed) or a gun from the store (which you buy with points, to outrun and push the zombies away (bullets just move zombies away, you can't kill another player). This is risky and often involves being chased by mobs of angry zombies.
If you have no good hiding spots and you're blocked out of most or all good bases, chances are you're not going to survive for very long. In this case, there are some different strategies you can use, those mainly being helping other players out by blocking them off, or going and putting other players in bad positions then waiting until you are zombified, then tagging those players as soon as possible. They deserve it.
So where do these pesky zombies come from? At the start of each round, a handful of players (depends on how many are on the server) become the Red Zombies, and they have to tag as many people as they can to keep their score (which goes down when you're a zombie, unlike a human's score) up to buy stuff for the next round. You can lower your chances of being the starting zombie by 75 percent by buying a pill from the store with points.
What do you do when you're trapped in a barricade and there's a Red? Try spinning at first (the sign to team), then, if that doesn't work, try breaking the barricade you made to get out-fast. You always know who the starting zombie is going to be because their skin goes pinkish-salmon.
What do you do if you are the zombie? If you feel nice, spin, then don't tag the people in the barricade. If you don't, tag them all (and try to do it all at once, when they're tagged, they can tag other people. But, of course, the best strategy (for you, and for them it's pretty good too) is farming. Farming is when you keep them all alive until the end (when they have a larger score for you to steal), then tag them. Then, you get more points, and they do too.
That is, of course, if you're in a barricade with other people. If you tagged them all, were going solo, or just running, and you turn red, there is no Mr. Nice Guy. There is no farming. It's just pray for speed and break as many barricades as you can and hunt them all down. (That's what you do if you're tagged, too.) Find. Chase. Break. Kill. The people have an advantage over you, being able to use guns and sticks and baseball bats and all that jazz, so you try and get to the front of whatever mob you're in to get the juicy meat bags first. There is no teaming as a zombie chasing a human.
That brings us to teaming. Teaming means you, when you're a zombie, don't kill a certain human, or humans, in return for them not killing you last round or next round or whatever. This can sometimes be mutually beneficial, but often doesn't work too well.
Well, that sums up my knowledge of this topic. If you have any more ideas or strategies, please leave them in the comments below.
The cooperative strategy