When you’re playing as a fullback and you get the ball from the centreback, what you’ll need to do is open your body up with a positive touch and you give it to your winger up the line, and then you have a few options.
Knowing what your winger usually does is important to pick up on and you can chat with them prior to the game, so you know how they like the ball, to which foot they prefer to receive it, et cetera.
After you pass the ball, the winger will usually turn and take on the defender but if he’s got a man marking him tightly, then you ned to show after you made the pass to support him from behind. As a simple support, he could drop the ball back to you, then you could bounce it up to the striker or you might have to play it back to the centre back, whichever option is best.
If your winger is able to turn with the ball and he starts to take the ball inside, to engage the defender, THAT is your cue to bust your ass to get around him in an overlap, to receive the ball and cross the ball or dribble into the box.
Becoming more prominent is the underlap as well. If your winger takes on a player, you might be able to make the run inside, then if he passes you’re in through the channel with your momentum headed towards the goal.
Here's a quick Demo of the movements on a board
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