I'am assuming you get confused by youtube videos by all the terms used. Forgive me if you already know this, but here are the basic terms used in flying

Elevator - Used for for Going :Up and Down
Ailerons - Used for tilting/rolling :Left or Right
Rudder/Yaw - Used for turning :Left or Right

Watch this - Bank Turns Explained

The guy explains it in a very simple manner. After you watched the video, if you need more clarification, read the following description he has given. If you understood, then don't bother reading it cause you might get confused.

Here are all the steps to doing bank turns.
1.Start going forward at about 5 mph. This will get the momentum you need to start the turn.
2.Apply a small amount of aileron to bank the quadcopter.
3.Continuously pull up on elevator.
4.Continuously apply yaw. If you don’t use enough yaw, your quadcopter will start falling into the turn. If you use too much yaw, then your quadcopter will lift out of the turn.
5.Use aileron to keep the quadcopter from raising or falling out of the turn.

Watch this, only if you haven't understood the above guy's explanation - Turning Tips and Techniques