When you start playing soccer, there are many things that can go wrong and that you can do wrong. But there are also a few things you can adjust right away to make a good impression and be mentally ready as well as physically ready for the game. A lot of the game is body language. So if you don't demonstrate to your team mates that you're ready, that you want to have the ball, that you are capable of doing something with the ball and you're willing to have it, then you have to adjust something. For example one thing, if you're moving around on the field, you can't be moving around flat-footed. You cannot have your head on the ground.
You cannot stare at the grass or anything else. You have to keep your eyes on the ball. You want to keep moving on your toes, because you never know when the ball's going to come flying to you and you have to make something out of it. Keep moving on the toes. Keep your knees bent to keep the balance more easily. Keep your arms bent to keep your balance more easily and protect yourself once you have possession of the ball. So there are a few things you can do to give the impression that you are already a more advanced player but also to not mentally fall asleep. The body can help you to stay awake, to be ready for the ball, and to be ready once you have to make the big decisions. This is the basic idea of how to get ready for soccer, the ready position. That's an easy thing to adjust and should help a big deal.