Perform regular backups of your database \ TLogs
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Depending on how many transactions your application is processing (and how much disk space you have etc!) you should be performing regular backups.
If you don't want this level of disaster recovery, you could consider changing your database model to 'Simple'. This means you'd only be able to restore your database to 'last known full backup', rather than point-in-time recovery that regular TLog backups offer. In this case, you should have an automated job that's creating a full db backup (maintenance plan etc)