Slip Stitch

I’m new here - looks like a great board. I’m doing a slipped stitch rib and the directions say to do a slip stitch. How do you know if you slip the stitch purl-wise or knit-wise in patterns? Or is the general rule to slip knit-wise unless otherwise stated? I’ve always wondered this and have been faking it for 15 years! LOL

IF you are doing something with the slipped stitch in the same row (ie, s1, k1, Pass the slipped stitch over) slip as if to knit

IF you are doing something with the slipped stitch in the next row (ie a slip stitch pattern) slip as if to purl.

UNLESS otherwise directed!