Apple Macs are just as easy to add to a network as any other device. You’ll still need a router or gateway as the hub of your network, and each of your Macs will need to be connected to this either via an ethernet cable or wi-fi.
All Macs have wi-fi built-in, though newer MacBook models may not let you connect to wired ethernet without an adaptor.
1) Find the network
When you first start up your Mac, it automatically scans for available wireless networks. To find out which networks are available, click the wi-fi icon in the top-right menu bar. Select the network you wish to join - in this instance, we're selecting the network that we named 'Hassle Free'.
If you've secured your network, you'll see a prompt asking you to enter the password or encryption key for your network. Do this, and tick Remember password in my keychain, so you can automatically join the network without having to enter the password each time.
2) Configure your settings
Alternatively, you can network your Mac by opening and clicking the Network icon.
Under 'Show', select AirPort and choose the wireless network you wish to join (enter any necessary passwords).
This window also contains advanced settings, though you shouldn't normally need to change these.
3) Share files and printers
Go back to System Preferences and click Sharing. In this window, you can give your Mac a name on the network and select the network services you require.
The most important ones to put a tick next to are Personal File Sharing, Windows Sharing (if your network contains PCs as well as Macs) and Printer Sharing (if you have a printer connected to your Mac that you want to share).