B.zang -- do you cut standing up or sitting down? I find I get better results standing up, as EasyPeezy said arm length is an issue for me. I also fold the fabric twice so I'm cutting through 4 layers. When I do a number of narrow cuts I check every 3-4 cuts that my fabric is still straight but unfolding a strip and making sure there are no Vs forming at the fold.

Between standing up and losing weight it is no longer such an issue, but when I was larger and sitting my tummy would get into the act as I leaned forward a bit...

I do like textured bottom rulers for my long cuts.

I went to a rotary cutting instruction class long ago at a fabric shop. An Olfa rep was vending and demoing Olfa products. She said when cutting with the rotary, always push down to the floor like the blade is going into the floor not run along on top of it. And the smaller the blade the less pushing the fabric forward when cutting. If the blade will not cut through two layers of fabric with very little effort then the blade is dull.

I had that problem even with 2lb weights on a long ruler. Then I noticed Donna Jordan puts one of the weights on the very end of the ruler farthest from her. I tried it and it made a big difference in keeping the ruler from moving at the end of the cut. My hand was then free to hold down the center more securely.

Great question. I've never thought of cutting sitting down except for when I'm trimming at my machine and do that with scissors. Reading through all the suggestions, I suppose arm length is my issue even though I'm not cutting to where I need to lean into a cut beyond the waist bend to access my cutting table. I've always thought by moving my hand to the upper part of the ruler I was preventing movement but I guess not. No amount of tip pressure by me prevented these tabs so I'm going to take all this advice into consideration. Thanks!