I've also been having issues with cutting straight strips lately. Just yesterday realized one huge problem- too much INFO! That's right I've been watching & reading about "correct" techniques for cutting. I've been sewing for & quilting for 44 yrs. with good success. Went back to cutting using my "incorrect" technique & wha-la - problem solved.

along with the little dots, I find the suction-cup handle (one you would put on your shower wall as a grab-bar) really helps to stabilize my ruler. They come in different sizes, too. Good luck!

If these are long cuts - do you "walk" your hand up the ruler? That helps to keep it straight.

I had this problem just yesterday, I had the screw on my rotary cutter backwards.

My hands are small so I have problems with the ruler. There is a clear sheet that you can buy that is suppose to help but the smaller the hands, the harder it is. So I have put felt pads every 1 1/2 inches on my ruler just on the edge I use for cutting. It also helps me know which edge to use since my ruler is 8 1/2 inches wide and I want to use the numbers starting with whole inches.

Also I am height impared. This also contributes to the trouble cutting. I am cutting on a table meant for an average sized person. The pads which I get at the dime store or Walmart are very thin and in the department that has the things to put on the bottom of vases and the back of frames.

Some people put on pad at each end. I put them all the way down. it helps my fabric from pushing ahead as I am cutting. Sometimes I just don't get that blade changed and just need to do one cut. That will sound familiar to a lot of us quilters.

I hope you have found a solution that works for you. There are many of us who have solved the individual problem we have.

There is a new ruler for cutting that has something that pushed down and grabs the fabric... I just ordered it and hope it works. I have arthitis and it hurts to push hard on the ruler. It's called "quilters slidelock", it's not cheap, but for some of us it is worth the cost.

Are you splaying your fingers on the ruler, cutting up level and then walking along as others have said? Also, keeping your little finger on the mat NOT on the ruler will stop it slipping.

I had that problem until I started putting sandpaper dots on the under side of my ruler. A dot of rubber cement in several places (let it dry good) works also and is less expensive. Then double check that you are using the correct measurement at both ends of the ruler. Put your hand on the end of the ruler closes to you. Cut as far as your finger tips and pause. Move your hand up and cut again as far as your fingertips. Keep going until you've cut all the way across. It seems slow, but you'll get faster and more accurate as you get used to it.

Is your ruler slipping around while you are cutting? I had this problem and tried the little dots, walking my hand, etc. none worked. I decided to try weighting it down and used large vegetable cans in plastic baggies so as not to mar the fabric. That was better, but not great because they were hard to manage with my arthritis. My DH suggested using my hand weights and that was the perfect answer for me. The shape of them makes it easy to move them and the weight 3 to 5 pounds are not too heavy.
Another problem was that the rotary blade was not smooth even though it was brand new. I bought another and it is fine. I hope someone's suggestions will help you end this frustrating issue. :)

I use the sandpaper dots, they work really well at keeping your ruler (s) stationary.