Need directions on how to replace gas control valve on a Whirlpool water heater

Not what you want to hear but;

Replace the water heater. By the time you purchase a new valve, (which hopefully no one is going to sell to you because you are not a licensed plumber) and hire a licensed plumber to install it you will have paid 3/4 of the cost of a new heater.

With that said, why do you think you need a new valve. Gas valves are very reliable and rarely go bad.

Gas is very dangerous if you don't know what you are doing.

I totlally agree with Harold here. Since your heater must be out of warranty it is not cost efficient or safe to try to replace the gas valve. Tell us exactly what the issue is that you are experiencing