In your browser, go to

wireshark.org$/$tools$/$oui$-$lookup. Notice that the OUI search field is located inside the gray box. The first three bytes of your MAC address make up the OUl of the device's manufacturer. Here is a sample address: $c8$:$f7$:$33.$ Type those numbers into Wireshark's OUI Lookup Tool and click Find. Minimize the browser.