Creative way to engage clients often?

For our dog training school, we’re trying to come up with a way to have our clients engage and think of us more regularly. One idea that came to mind was to do a weekly giveaway, but what I’m trying to look into more is to make it so clients have access to time limited offers that rotate/change each week, or perhaps every day.

This is all in the hope that they’ll wonder what today’s deal/offer is and visit the website to claim. Any thoughts on what would be the best way to make this possible?