Create a computer-to-computer network on Mac
If you want to set up a temporary, ad hoc Wi-Fi connection between your Mac and another device, you can create your own network using the Wi-Fi menu.
Create an ad hoc network
On your Mac, enable legacy networks.
Click the Wi-Fi status icon in the menu bar, then choose Create Network.
Enter a name and choose a channel for your network.
Click Create.
When you create a computer-to-computer network, the Wi-Fi menu icon changes to show a computer . The new network is available in the Device section of the Wi-Fi menu.
Connect to an ad hoc network
After you create an ad hoc network, you can connect to it from another Mac.
On the other Mac, enable legacy networks.
Click the Wi-Fi status icon in the menu bar, then select the ad hoc network.
Enable legacy networks
On your Mac, choose Apple menu > System Settings, then click Wi-Fi in the sidebar. (You may need to scroll down.)
Click Advanced on the right.
Turn on “Show legacy networks and options.”
Click Done.