Here is my new and different way of making an 3-stitch i-cord cast on:
1. Cast on 4 stitches.
2. Slide the stitches to another dpn or to the other end of a circ (just as you would to make an unattached i-cord).
3. k3
4. Wrap the yarn around the LHN (left hand needle) as in the picture by wrapping the yarn over the needle from the back and then under the needle again. The yarn starts out in back and ends in the back of the work.
5. Slip the 3 stitches on the RHN (right hand needle) back to the LHN purlwise.
Repeat steps 3 - 5 until there are the LHN has on it the desired number of stitches to be cast on plus 2.
To end, you can then k2tog, k1, return the stitches to the LHN, k2tog, and then return this stitch to the LHN.