|You download the user manual which has all the instructions you need. That is as long as your router has not been loaded up with any of the third party firmwares that seem popular with owners of that model.|
By the way, you don't need to reset the security key. You only need to log into the admin interface to view the key in plain language. The manual will tell you how to do this. Hopefully when you set up the SSID & Security you left the admin login/PWD at default settings or can remember what you set them to, Otherwise you will need to do a full reset.
Goin' Fishin' (Some day)