You can do this by going to their patient profile and unsubscribing them from certain types of communications.
You can click on the patient's name after searching in the Home tab
Or in the Patients tab
Or by clicking on their name in blue font as it appears on other pages.
You can edit opt the patient out of certain communications in the "Communication Preferences" section.
Click "Edit" next to the communication mode, then uncheck anything the patient doesn't want to receive. Then, click "Save."