How do I set up a password on my Netgear router? I no longer have the manual and it model # is WGR614.

Type "WGR614 manual" into Google. The first link is the manual. Let me know if the manual doesn't contain your answer.

Netgear passwords are printed on a small label on the side of the router,if you did not remove the label already. I don't believe you can change the password if you forget the stock one that came with it. Try this Default Password for NETGEAR Devices

Plug your PC directly in to the router, and set your PC to obtain IP automatically. Once it has established a connection to your router, open a command prompt and type in ipconfig and press enter. You should see an IP address for your default gateway. Open a web browser and type in the IP address of your default gateway. This should bring you to your routers web interface. If you already know the password to get in to it, it should be pretty easy to change the password you want. The manual Zylstra pointed you to should assist you on how to change the password.