A k2tog makes a right leaning decrease. When I knit left handed, my stitches lean toward the left. I'm not sure if your setup is the same. So you may need to adjust. Okay, here is what I do. With the working needle in your left hand, slid the needle into 2 back loops. Bring the working yarn under the needle, over the tip & thru both loops on the needle. Slide the 2 stitches off. Two stitches have been worked into one. The decrease leans right.