Depending on your event/campaign use filters with meaningful criteria such as spending amount, age, location, gender, stores etc.
According to theme of the campaign/event (birthday, mother’s day, valentine’s day, back2school etc) choose a premade template and customize it by entering the text, your logo and images.
After your template is ready just click send and that's it! :)
Measure your impact by analyzing open rates, bounce rates, clicks for offers (via gamification etc) for SMS/mail. Get more insight on what works and what doesn't.