What is a one-sentence summary of the following article?
Once you've changed the hardware router password, you need to create a username and password to access the wireless network. On the Linksys admin screen, click the Security tab. Click on the Wireless tab, and then click the Wireless Settings tab. Next to Configuration View, click the Manual radio button. If you don't see the Manual radio button, scroll down until you see the Wireless Security section. Click the Security Mode dropdown menu, and then choose a security type. WPA2 is the most secure, but WEP is more compatible with older machines. It's recommended that you use WPA2. If that doesn't work, use WEP. In the Passphrase field, type a password you'd like to use. Click Save Settings. When you connect to the wireless network the first time, you'll need to enter the password you chose.

Summary:
Go to the Linksys Security page. Choose a security option. Choose a security setting. Enter a passphrase. Connect to the internet through your wireless router.