Do not know how to work power washer

Dear Carrie688,
I cannot for sure understand your problem. You say, you do not know how to WORK power washer. Does WORK mean FIX...or USE???? I will assume that you wish to know how to use it.
First without water connected and without gun connected...switch on the machine. If it turns, then this means the electric motor is OK. Now connect the hose and gun. Connect water supply. Now always start the machine with gun open. This will help to remove air from system. When pressure builts up, close gun, and machine must stop instantly. If machine does not stop, open the gun again and switch off the machine. If the machine continues working when the the gun is closed, this will result in a lot of damage. I do not know what model you have, because also there are old models that when gun is closed, the machine keeps running. I assume your model is recent. So the machine will stop when gun is closed. Now when finished, switch off machine and electricity. And most important release pressure from gun. Do not store machine with pressure still in it. This will damage machine and it is not safe.
Now if you have detergent, this can only work on low pressure. There are bigger machines that detergent works on high pressure. But the normal system is that detergent works on low pressure. Also before storing, pass fresh water to remove all detergent from pump of machine. Never store a machine with detergent in its system.
Regards,
Fulltech.