how to wire a 220 volt 50 amp circut?

Bare wire is ground, white wire is neutral, line wires are other colors except green, hook the lines to the breakers, Observe the required codes for grounding and ground fault circuit interrupters that are required for the spa/ hot tub. Use wire of a large enough size to handle the ampacity, run the wire according to code. Buy all permits needed and have the system inspected when completed. When all of this is done, you either have passed the inspection or not. If not do what you did not want to do in the first place. Hire an experienced, qualified, professional electrician. Faster, easier, safer and probably cheaper in the long run.

Call an electrician. There are many code requirements for hooking up a 220 volt spa. And, if you do it wrong, someone could get killed or you might start a fire, and your insurance wouldn't cover it because you didn't have a licensed contractor do it to code.

If you don't need people telling you to call an electrician, then why do you need this question answered at all. Obviously you don't have the knowledge of a professional or you wouldn't be asking here.

I'm not trying to be mean, but asking people for help then telling them what type of help they can offer isn't good.

So my advice is, hire an electrician.

Codes almost everywhere require you to obtain a permit to install a 220 circuit. If you do it yourself it could void your home warranty your home insurance and your life.