Snapshots are on-demand disk images of DigitalOcean Droplets and volumes saved to your account. Use them to create new Droplets and volumes with the same contents.
To migrate a Droplet using snapshots, you should:
Create a new Droplet from the snapshot in the desired region or from the desired account.
When you create a new Droplet from a snapshot, you can also increase the size of the Droplet. Your SSH keys are transferred to the new Droplet along with all the user accounts from the time the snapshot was created.
The data and organization of the file system on the new Droplet should be identical to the original. However, it's a good idea to test the services on the new instance because, for example, it's possible that services you expect to be running weren't set to start at boot. If you're using a floating IP, a fast way to test is to update floating IP to point to the new Droplet. If you notice any part of the migration has failed, it's equally fast to revert back to using the original Droplet.
After any migration, it can be worth the cost to retain the original Droplet and snapshots, run automated and manual tests, and seek stakeholder verification. This way, if something goes wrong in the new location, these backups can be used to determine if the problems existed before the move.
Once you've verified that the system works as expected, you can take steps to move it into production. For example, if you had a domain name directed to the original Droplet, you'll need to update its DNS records to point to the new IP address.