You can enable backups during Droplet creation.
To create a new Droplet with backups enabled, from the control panel, open the Create menu and select Droplets. Choose the distribution and Droplet size that fits your needs. Under the Add backups header, click the Enable Backups button:
Once you have selected any other options, choose a hostname for the Droplet and click Create.
If you’re using the API to create a Droplet, you can enable backups by adding
"backups": true to the request body.
You can enable backups after Droplet creation using the control panel.
To do so, navigate to the list of Droplets for your account. Click the Droplet name for which you’d like to enable backups, and then click the Backups menu item.
Click the Enable Backups button to enable backups.