When you starting a battle, especially 1v1 battle, make shore you starting with "Mike It Rain". this way you can prevent the enemy from escape.

If you are after an escaped enemy, and he is too far to your range, you can shoot with Double Up on a closer enemy. the bullet may be get from the target to the escaped enemy, and kill him!

Remember that your ultimate ability dale a lot of damage just if the anemy stay a lot of time at it's zone. Best leave the Ultimate to the end, the point where you're sure it will kill someone.