Show the hordes of zombies that your base is not one to be trifled with in YORG.io. Start with only a base, and expand out by building resource-gathering structures and defenses to keep them safe.
Watch out when night comes, because that's when the zombies come to munch on your brains.
There's a great tutorial that will ease you into the game. But basically click structures and place them according to your base layout, and your nearby items.
Don't go crazy with defenses. Getting a sizable resource income is paramount. Just build defenses according to where they're needed.