this post expands a bit more on mac address spoofing
Sure you can enter random mac addresses, but I always believe its better to collect and use somebody else’s mac address, you see there are websites and databases of mac addresses and vendors you can look up a mac address using this WEBSITE

there are programs and apps to easily scan and collect mac addresses such as NetStumbler and Wiggle for Android

Then there are network scanners that will scan and log the mac addresses of the networks you are attached to such as Network Scanner for Android and software like MAC Address Scanner

lets say you connect to a network, did a scan, then cloned the mac address of a connected system such a laptop or ipad, then you spoofed your user agent to match “See Firefox section of our website” the chances are the man will be looking for that device, not your own when they try to trace who was on the network and did such protesting online.

never ever use your own mac address and verify that your new mac address updated by a few simple commands such as ip config /all for windows and ifconfig -a for linux