Proceed by camouflaging yourself in the paint.
When you reach the danger zone, wait for the red warning to pass. Otherwise, you cannot camouflage and enemies will see you and open fire.
When you camouflaged, you can shoot at them as they pass through the danger zone.
By the way, your tiny clone minions are pretty tough fighters. Use them a lot.
Don't forget to stop by the upgrade units for many of your abilities to upgrade.
Thanks to them, you will be able to capture the towers faster and easier.

Super addictive and fun gameplay.
Enjoy!