1. Run multiplayer
2. Join a server on Recruit or Regular difficulty mode.
3. While you in game, press Tilde ("Commanding mode") and hold it.
4. Start moving your mouse over houses, bushes or every places where you expecting to find the enemy.
5. Once you found the place with the enemy, stop your crosshair on him and you will see his exact position, you will see that your crosshair became red telling you that he is enemy for sure, you will see the range to him.
5.1 If you are a sniper and you want to check the range to your target, just move your crosshair on him, press Tilde and you will see the correct range to your enemy. Use this information to correct your rifle's distance setting.
6. Shoot him and probably he will call you a cheater. But we know that you are not. You are just a bug-user.