Slip 1

when a pattern says to ‘slip 1’ like in skpo (slip one, knit one, pass one over) what is the rule about the direction of moving the ‘slip 1’…is it enter like for a purl stitch or enter like for a knit stitch?
advice please? I hope I made myself clear

When you slip the stitch for a s,k,psso, slip it as if you were going to knit it.

For just slipping a stitch, slip as if to purl.