What you're essentially doing is twisting these two stitches (it's like making a tiny cable). You're going to skip a stitch and knit through the next one on the needle, but don't drop it off yet. Then go back and knit the first stitch on the needle (the one you would usually knit), then slide both stitches off the needle. Try it and see if it makes a little twist. And if my attempt at explaining doesn't help, let me know and I'll try again!