Hint: Turret gun zoom:
When you get to use a turret gun in certain parts of a level, click Left Analog-stick to zoom in 3x. This will help you see what you are shooting at, and result in better aim.

Hint: Weapon zoom:
On most weapons, you can zoom in by 3x pressing R.

Another way to zoom in is to click the Left Analog-stick up to three times.

Hint: Easy Skynet Tech points:
While zoomed in, aim for the neck of most enemies and their heads will pop off. Each head is worth Skynet Tech points.