Here is a simple starting strategy.
Solo - Put the first generator on before the zombies spawn on round 1, stab all of the zombies on this round.
On round 2 grab the x2 out of the reward box and put 4 or 5 mauser shots in to each zombie and stab. On round 3 grab the m14 off the wall and put 2 shots it each zombie and stab, you should have between 4 and 5k points so leave a zombie and head through the first few doors to get to generator 2 and turn it on. Grab an mp40 from the tank station and go through the workstation to generator 3, you may need to kill a few zombies before you go here if you do not have 2000 points left for the 2 doors.
From round 4 you can camp or train near speed cola in the footprint for easy headshots and you can easily make 20,000 points here (depending on how long you want to stay here) before you go to no mans land. As long as you don't open the door to no mans land you can stay near speed cola until you decide to get juggernogg, the Panzer does not come until round 8 with the door open but you can keep that door closed longer and he won't come until you go to no mans land. I leave a zombie before opening the no mans land door which makes killing the panzer very easy with any weapon as long as you keep moving side to side to avoid his grip. Try not to kill the last zombie while shooting at the panzer so you can easily turn on generator 4 and buy juggernog.
Depending on which round I leave speed cola, I usually have enough points to turn on all the generators and hit the box a few times.
@ Janitor_Lloyd - Zombies only die when injured if you move too far away, if you think your zombie may be injured you could try digging up another zombie.