It's hard to describe.... I'll try but this website has good pics.
Lion Brand Yarn Company
Knit the 1st stitch like normal, knit the 2nd but leave it on the left needle...
take the 1st stitch you knit, slip the needle into it and slip it over the 2nd stitch, landing the 2nd one on the needle and keep going like that. You'll only have 1 stitch on the right needle at a time.
I'm sure I didn't explain that right.