A medium, or medium soft mattress, is recommended as they allow plenty of give to contour to your body's natural curve and keep the spine aligned while providing maximum comfort.

Due to your vulnerable pressure points, side sleepers are best suited to softer mattresses that give you more cushioning and allow your body to sink slightly into the mattress.

The vesgantti mattress nice semi firm yet still soft support. It's hard to explain but it feels very soft to the touch but isn't too soft when you lay on it. It's a nice combination of soft and semi firm. 

side sleeper mattress

This mattress helps support all of my bony prominences, supports my head, neck, shoulders & lower back .