Instructions
Turn on your Nintendo DSi. Tap on the wrench icon in the touch screen's application list to access the console's system settings.
Tap the right arrow twice to reach the third page of the system settings menu. Tap "Internet."
Select "Connection Settings." Tap on "None" next to "Connection 1."
Tap on "Search for an Access Point." The console will look for wireless access points in your area.
Select your wireless network. Look at the lock that appears next to its name to determine its security settings -- an open lock indicates no security, a closed gold lock indicates WEP security and a closed silver lock indicates WPA security.
If you have no security on your network, select "OK" and tap on "Save Settings," then choose "Yes" to test your connection.
If you have WEP security, enter the password for your network when prompted and tap "OK." Select "Save Settings" and tap on "Yes" to start a connection test.
If you have WPA security, tap the "Back" button two times to return to the "Internet" screen. Tap on "Advanced Setup." Select "None" next to "Connection 4." Tap on "Search for an Access Point."
Select your network name, which will now have a gold lock. Enter your WPA password and tap "OK." Tap "Save Settings" and choose "Yes" to begin the connection test.