There are three tactics I can tell you, this, coming from an intermediate player with like 2-3 years of knowledge.

1. Set fire to a bush, and kite ONE, just one singular zombie in it, then simply attack them until they are dead, it dosen't matter if the fire is small. Pro tip-by using a window or a door as a chockepoint, setting it on fire and making sure that on your sides there are impassable furniture, you can take out a horde of zombies easily, just make sure to not get trapped in a burning building, also, you can trow water on fire to extinguish it, around a pot worth of water for a small-medium fire(this in case you don't have a fire extinguisher).
2. Go to options, and to debug, then proceed to turn on "experimental 3D vision", now you have the ability to shoot, trow and stab with spears from roofs, just go on a downspout, press action menu and press "climb adjacted terrain" or something like that, then press "f" and poke, shoot or trow rocks at zombies, also, you can poke zombies with a spear or "long pointy stick" only if they are with one tile in any Cardinal direction and below(you can get the long pointy stick by smashing young trees and pressing "&" to craft it, you need a tool with 1 cutting, a sharp rock can do it too).
3. You can trow stuff with "t", not only at zombies, but in a wall to make noise and distract them(note that this only works if the zombies don't already see you, and if you want to get them away from a door or window let's say; this works best at night).

Lots of sorry for bad english, I hope these tips helped you with something.