Help working at a gas station?

How do you know for a fact that the manager is nasty? How do you know that the customers are rude? It could be true, but you are listening to third hand information that is poisoning your mind before you begin. Ask the boss what chores you can do to stay busy. Let the boss tell you what she finds most important this way, then do what she says. Keep a positive upbeat attitude. Even if you are feeling insecure or bad, never let it show at work. If your manager puts you down for no reason, thank her for pointing out your flaws. A therapist taught me that, it disarms the boss (I loved the shocked look on my former boss's face when I did this.) Don't take yourself too seriously and continue to hold on to that upbeat attitude. That will help you through the stress.