The first step is to download the Netflix channel from the Wii shop, and then follow the setup steps to watch movies and television shows from the Wii. Slower Internet speeds could delay the download and compromise the viewing abilities once the system is setup, so take unnecessary items off the network when watching movies to help speed it up.
After downloading the Netflix channel, go to the home screen and select it. Once it launches, select start to enter the channel. It should pull up a screen with the 'Member Sign In' prompt, so select that and enter the Netflix email and password. This action logs users into their Netflix accounts and will pull the data from Netflix's website to the Wii, allowing users to watch items from their queues through their Wii's.