I probably receive more Texts than phone calls on my iPhone these days. Lately, I have been assigning specific Ringtones to the Contacts that call or text me the most. This really makes it easy to differentiate between important calls and texts and the very annoying Spam calls and texts. If assigning specific ringtones to calls and texts would be helpful to you, then read this article for phone call ringtones and this one for text ringtones. They are both similar, but slightly different in their setup.