If both of the Macs that you're attempting to transfer data between are fully functional, the best way to achieve this is to use the built-in Migration Assistant application. This ensures that data is moved correctly and will appear on the new Mac in exactly the same locations as they appeared on the old one.

One minor thing to note is that this method will not move over any applications, transferring applications can result in compatibility issues so we only transfer files. If a user has applications on their toolbar, they will appear as a blank ? icon on the new Mac after the transfer, you can hover over the icon to see which application it should be. Applications can be re-downloaded once the transfer process is finished and will take the place of the ? icons once the download is complete.

Initiate the Transfer

1. Power on both Macs and log in to both.
2. You have two options to connect the Macs:
   • the fastest option is to use a Thunderbolt cable and physically plug each end into both Macs.
   • If you don't have a Thunderbolt cable to hand, you can perform the transfer via WiFi, if you use this method, ensure that both Macs are connected to the same WiFi network.
3. Open the Migration Assistant application on both machines (You can use Command + Space to Spotlight search for the program if needed)
4. On the New Mac, choose the option to transfer From a Mac, Time Machine backup or Startup disk and click Continue. 
5. On the Old Mac, choose the option to transfer To another Mac and click Continue.
6. Back on the New Mac, you should see the Old Mac appear as an option to transfer information from, select it and click Continue.
7. Verify that the security code that will now appear on both screens is identical, then click Continue on the Old Mac.
8. Back on the New Mac, you'll see a screen similar to the one below, make sure to uncheck the Applications folder, and the MERIT Admin user profile, keep everything else checked, then click Continue:
9. You should see a popup asking whether you want to Rename or Replace the user account on the New Mac, this appears when the user you're trying to transfer has the exact same name as the user that's already on the computer. As the account on the New Mac won't have any actual data at this point, it's safe to Replace, so choose that option.
   • (In the rare event the New Mac has already been used prior to performing this process, ensure that any files the user created on the New Mac are backed up before doing this. You can add those files back manually after the transfer is completed)
10. The transfer should now begin, you'll need to leave the computers alone for the duration of the transfer. If using a good quality Thunderbolt cable, and transferring around ~200GB, the process should take no more than 10-20 minutes. The transfer time is dependent on a variety of factors, from the total size of the files to transfer, to the size of those individual files, and even the Mac hardware itself and the cable you're using if using a wired Thunderbolt connection. Worst-case, this process could take hours, so if that ends up being the case, it may be a good idea to attempt the process as the end of the day and let it run overnight.
11. Once the transfer is complete, you can quit the Migration Assistant on both computers.
12. On the New Mac, go ahead and log in to the newly-transferred account, everything should be exactly as it was on the Old Mac, and ready to use immediately. As mentioned before, the main exception will be Applications, you'll need to re-download any applications that don't get automatically installed as part of our standard imaging process, common applications that need to be re-downloaded are web browsers such as Chrome and Firefox, and Adobe software such as Acrobat (To re-download Adobe software, you can do so via the Adobe Creative Cloud application, which should be downloaded automatically).
    • If you needed to back-up files on the New Mac as mentioned in Step 9, you can go ahead and move the backed-up files back to the New Mac by dragging and dropping them into their respective folders.

If the Old Mac no longer fully functions (For example, it boot loops), then options for data transfer become limited. The main options are as follows:

Migration Assistant

It is still possible to use Migration Assistant in this case, albeit in a much more limited capacity. You have two main options:

1. If you're able to keep the Mac switched on for an extended period, you can give Migration Assistant a try as detailed in the Transferring Data Between Two Functional Macs section. You can try booting the Mac up in Safe Mode and access Migration Assistant that way.
2. If that isn't possible, you will need to utilize Target Disk Mode. You can still use Migration Assistant this way, but you will need to use a Thunderbolt cable to perform the transfer, and the results may not be as clean as some files may not end up where you expect them to. To attempt this, you'd perform the steps as outlined above in the Transferring Data Between Two Functional Macs section, but in Step 1 when you boot up both machines, you'll boot the Old Mac into Target Disk Mode, and ignoring any of the steps that require interaction with the Old Mac. Depending on the age of your Mac, you'll access Target Disk Mode in one of two ways:
   • Most Macs will be using an M-Series chip, to access the Recovery Menu on an M-Series Mac, with the Mac powered off, hold the power button until the Recovery Menu appears. Once you're in the Recovery Menu, click on Options and then Share Disk.
   • If the Mac is older and using an Intel chip, to access the Target Disk Mode on an Intel Mac, with the Mac powered off, hold the T key while you turn the computer on until Target Disk Mode appears.

Manual Transfer

1. The final option would be to perform a manual data transfer. To perform this, you'd need to start up the Old Mac in Target Disk Mode using the instructions above in the Migration Assistant section. Once you've done this, you'll need to connect both Macs together using a Thunderbolt cable, then access the Old Mac as if it were a hard drive using Finder on the New Mac. At this point, you'll just drag and drop the files from one Mac to the Other.