Crocheting into the "same stitch"

[Fantine]

I have a general question involving the right way to "crochet into the same stitch." I frequently see directions that tell me to connect the ends of a round with a slip stitch and then to do a SD (or a DC) "in the same stitch." How exactly do I do that? I can't figure out what loop I'm supposed to be using. Can anybody give me some information or maybe a video? This has been bugging me for some time now. Thanks.

Just to clarify, I understand how to do multiple stitches, what I can't figure out is how to do a SC or a DC "in the same stitch" after a slip stitch or a chain.