To set up a protected Wi-Fi network, turn on the firewall, activate the encryption, and change the default password. Change the password periodically, using a combination of letters, numbers and symbols. Use both uppercase and lowercase letters, and avoid any common names or words in the password.
A Wi-Fi network becomes protected when the encryption is turned on. Many new wireless routers are set with this feature disabled, so double-check that it is turned on. Read the manual to find out what type of encryption is available. Some common ones are WPA2 and WEP. Choose a wireless network password when you activate the encryption. Create a reminder to change this password every few months.
The firewall also needs to be turned on, though this alone is not enough to have a completely secure network. As with encryption, this feature comes with wireless routers, but it is often turned off initially. Change the default name of the wireless network to protect your personal privacy and keep others from knowing what type of network you're using. Change it to something unique, but not something that gives away the owner of the network. Do not use a name of a family member or a business name.