STEP-BY-STEP SSK SLIP, SLIP, KNIT
1 Working with the yarn at the back of your knitting, insert the point of the right-hand needle into the next stitch as if to knit, but instead slip the first stitch onto the right-hand needle.
2 Now slip the next stitch from the left-hand needle onto the right-hand needle in the same way as for Step 1.
3 Push the point of the left-hand needle through the front of both the slipped stitches.
4 Bring the yarn around just as you would for a knit stitch and knit these two stitches together. You will now have a single stitch on the right-hand needle, and your two slipped ones will create a left-leaning decrease.