Pattern/ Increase Question

I’m working a cardigan pattern. The cardigan is in stockinette stitch. As I progressed through the pattern, I came to instructions for the increases. The pattern simply states “inc in rev St st.” I know that that means “increase in reverse stockinette stitch.” What I don’t know is what that actually means (i.e. M1L, M1R, KFB, PFB, YO???). What increase do I use for "inc in rev St st?

You could do a pfb. Presumably this increase is on the purl side of the reverse St st. Or you could do a make one towards, M1T.

Thank you for helping.