We recommend scheduling your backups for times when the traffic on your site is light. The following are recommendations for Database Only and Complete (Full) Backups.
Database Only Backup: Weekly
We recommend performing a Database Only Backup to back up your database on a weekly basis since your database changes much more often than your files and folders.
If your site has new posts/pages created daily, you may want to consider having Database Only Backups ran daily instead of weekly. As the database is usually very small in comparison to the entire site.
Complete (Full) Backup: Monthly
BackupBuddy recommends doing Complete (Full) Backup every 2-3 weeks since your files only change when you add or upgrade plugins, themes or your WordPress version.