I'd simply do the following:
Create a selection list for the data you wish to backup.
Create a B2D location (device) to store your backups
Create a media set called dailies, which has an Overwrite Protection Period of 6 days, and an Append Period of 1 day.
Create a media set called weeklies, which has an Overwrite Protection Period of 4 weeks, and an Append Period of 1 day.
Create a new policy.
Add a template to the policy which performs full backups, targetting the weeklies media set. Set the schedule to be each Saturday.
Add a template to the policy which performs incremental backups, targetting the dailies media set. Set the scedule to be each weekday.
Apply the policy to the media set you created in step 1.
That will (roughly) replicate what you do to tape. It's fairly straightforward to modify the policy and the templates if needed, and if you still want to backup to tape (for example to take offsite), then it's simple to add a duplicate data template to the policy.