Your primary goal should always be destroying the points. Until you do that, the zombies will continue to spawn indefinitely, so there's no point in waiting.

Make sure you use those special weapons carefully. They don't cost any courage points, but they are fairly rare.

Some troops are more effective against specific types of enemies, but you will have to figure out by yourself.

In order to unlock new locations, you need gas and waiting for it to replenish can be quite boring. So, when you get a chance to unlock a new area, choose a rich location with a lot of potential.

Upgrade your units as soon as you get the chance because the farther you go, the more difficult the enemies will be.

Remember to keep your eye on the health bar in the top right corner. A lot of players get into the action so much that they forget about the health and end up dying unexpectedly.