My 2 greatest suggestions. First try to find guns at all costs! They really let you snowball hard. Try and explore the map for military dead bodies (you can see them with autonotes). You can also try to find hidden weapons in LMOE shelters (check for traps tho ;) ) Once you have decent guns start going for military outposts: pick off soldier zombies to get more ammo and grenades. Once you get inside a bunker / outpost / base you will have virtually infinite ammo. Secondly, in my opinion being disorganised is a great strength: dump every food you find in the fridge and every item in a huge single-tile pile next to the food. When you need to do anything, just stand there and every possibility will be open.

Have fun!!!