While the rocket launcher is one of the mostly weapons in the game, it's good to know how to use it to its full effectiveness.
First, the rocket is great for destroying enemy controlled vehicles, due to its speed and locking ability. However, you have to know when to fire and when not to. Targets moving perpendicular to your position have a good chance of evading the rocket, due to the rocket's wide turning radius. Use it when the target is moving slowly relative to your field of fire, such as towards you or away from you. Also, make sure there is no obstruction between you or the target, such as a hill, that could intercept the rocket.
When using the rocket against foes on foot, the key is to lead the target. If the target is strafing, fire the rocket at where they will be when the rocket reaches them. And always aim for the ground when possible to utilize the rocket's
spash damage; It is too easy to miss the profile of a moving target, even at close range.
Remember, due to the rocket's small clip, it is important to make every shot count. Like the fuel rod gun, the rocket has a powerful melee, but you should never have to use it.