You should establish a regular procedure for backing up your data. Backups are the only way to ensure the security of the accounting records you store in Sage 50. Without backups, you run the risk of losing weeks or months of work.
How often you back up data is up to you and depends on how you use Sage 50. If you enter transactions in a batch, every two weeks, you can get by with backing up every two weeks. If you enter transactions daily, you need to establish a daily backup routine.