How do I password protect the wireless signal coming from my Linksys router?

It's a Linksys WRT54G Wireless-G Router, it was kind of a hand me down from a friend so I don't have any software that may have come with it.|||You can go to the Linksys site and get the complete information for the unit. To use WEP or WPA you go to the wireless security and make it active. You then select the type and enter a code generator that will give codes you can use to connect the wireless device with. Be sure and Apply the settings. Also, change the router login password.|||Enable WEP or WPA security in the HTML setup and you will be prompted to enter a pass phrase.|||Generally it's the same address on all routers. Point your browser to 192.168.0.1 and the settings are easily navigated with the menus.