how do you mark notches1 How Do You Mark Notches?

How do you mark notches? This question came up when I was cutting fabric for a mock-up at work. I, like I always do, marked the notches by cutting a slit halfway into the seam allowance. My coworker, however, suggested that I cut exterior triangles (the triangle would point away from the pattern) on the perimeter of the pattern that would be trimmed off after sewing. Her reasoning was legit – marking notches her way prevents from cutting too far into the seam allowance and sometimes into the actual garment. Even though it is a better way to work, I have stuck to marking notches with slits for no other reason than habit but maybe I should consider a change. How do you mark your notches? Do you cut exterior or interior triangles or do you cut slits? Maybe you have a completely different method of cutting notches that I’ve never heard of. Please do share…