Access the web-server interface inside the router, and change the SSID to a value that _only_ you know, and set the router to _NOT_ "broadcast" the new SSID. Enable encryption, and choose a password for the encryption.
Then, any wireless device that wants to connect would need to _know_ the SSID, and then to _know_ the password.
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Access the web-server interface inside the router, and change the SSID to a value that _only_ you know, and set the router to _NOT_ "broadcast" the new SSID. Enable encryption, and choose a password for the encryption.
Then, any wireless device that wants to connect would need to _know_ the SSID, and then to _know_ the password.