HiCan anyone tell me what the following means and how I would do it?
K10 sl 1 knitways, K1, psso, turn
Knit 10 stitchesMove 1 stitch from the left needle to the right needle as if you were going to knit it, but don't Knit the next stitchNow use the left needle tip to Pass the Slipped Stitch Over the one you just knitted (a decrease)Turn your work.
You can see a demonstration of the psso here. Just scroll down a bit, and it will be on the right side.