A marketing strategy needs to incorporate three things. Attracting new guests, having repeat guests return more often, and having current guests spend more money.
Having guests return more often can be as simple as a parting salutation to include an invite to return.
"Please Come Again" is three words that you don't always hear as you finish your dining experience. You hear "goodbye" and "thank you," but the invite to return is commonly missed.
Make your guest feel like you want them to come back, and they might come back sooner than later.