There isn't much difference between the circular and the flat version of this stitch - all you need to remember is to put the stitch marker back in the correct place, and twist the first stitch of each new round.
When you come to the end of each round, you will need to slip the last stitch before the marker off the left needle so you can temporarily remove the stitch marker (or, use one of the stitch markers that opens and closes like a safety pin). Once the stitch marker has been removed, slip the stitch back to the left needle, and either k2tog or k2tog tbl, depending on which round you are working on. If you do not do this with the stitch marker, you will be moving the beginning/end of your round each time you complete a round - I show this in the video.
Once the stitches have been worked, you need to put the marker back on. Slip the first stitch on the right needle off, place the marker, then slip the stitch back onto the right needle.
Now, you will need to twist the first stitch on the left needle before proceeding with the next round. This is shown in the video, and is really simple.
As with the flat version, this is worked on any number of stitches, and you will be repeating two rounds.
Round 1: *k2tog, slipping only the first stitch from the left needle
Round 2: *k2tog tbl, slipping on the first stitch from the left needle
That's it. Here is the video. Happy Knitting!