The most important thing is to have either; A: Good Chain/Gold or higher tier armor B: A stone/iron or higher tier sword (not hatchet)
The second most important thing is that you attack before the night because otherwise the chests get refilled and they will become tougher to deal with
Once you have checked off both of these things you are ready, remember being in a team means they have to share their loot either that or their will be one strong one and one/two weak one's.
If they are sharing they will most likely both run at you, if this is the case just keep spamming click and jump in between them, you will find they hit each other a lot.
If not its gets a tad more difficult, the stronger one (most likely iron) will try to run at you head-on while the weaker one (most likely wood/leather) will either sit back and bow you or cut you off. The best thing to do in this situation is run around in circles while the stronger guy chases you eventually the weaker one's will get tired and will come in to help. If you are good at flanking just hit these one's as much as possible while flanking the other guy. Eventually after you have those kills under your belt surprise him by turning around and kicking his ass.
Also after taking down a team of more than two people you are pretty much set gear-wise