Can anybody hlelp me? I seem to not be able to cut fabric, I have a cutting board rotary cutter (new blade) and non slip rulers always measure twice and cut once no 2 pieces are they same. My friends say I am being too picky any help gratully recieved

your not being to picky..how many layers are you cutting?

You may (possibly?) be 'tilting' the rotary cutter onto it's side juuuuuust a weeeeee bit.
Get a 'June Taylor Shape Cut'. Get the largest one eventho it is a few dollars more. You will not regret spending those bucks. I promise!
The June Taylor Shape Cut has slots in it for you to run your rotary cutter through. The long rulers never fail to slide (for me) and I just can't get a straight cut using them. Just can't!.
Stand your rotary cutter blade straight up. Practice on scraps or aliminum foil (sharpens your blade at the same time). Watch your blade as you cut and you will see when it is standing the way it was designed to.
A second thing you can do is be sure you have the rotary cutter screw tightened enough to hold the blade but not so much that the blade won't roll when you are pushing it across the fabric.
Another thing is the lint that builds between the blade and cutter. Take it apart every now and then, kleenex the lint off and put a drop of machine oil on the round part of cutter where your blade (lies?) lays. (You can put it on that part of the blade instead but don't cut yourself. Extra careful!).
Can't wait to hear you got the hang of it./Regards, Dorothy

Good advice Dorothy!

When I first started cutting my fabric I had the devil of a time using just a ruler and a rotary cutter. I bought a Fiskars paper cutting board with the rotary cutter attached. Easy peasy. Works great and is safe for even my DGD's little hands. I still do a little rotary cutting but I like this method better even more than the JT Shape cut.

I agree with DSB that 'maybe' you're tilting the rotary cutter left or right without realizing it.

How much are your 'off'?

even "non slip" rulers slip. I have to lean HARD on mine to get them to stay still while I cut.

Are you using the same ruler?
Are you lining it up the same each time?

I went to a workshop with Pat Speth and she gave us each a little (3 inch) piece of the rubber shelf liner to put under our rulers. Works like a charm. (However, I now have 2 triangles....can you guess?)
Another thing that I have discovered...I had a ruler with a lip on it to use like a "T" square. It wasn't square. It would be off by 1/8 inch every 18 inches. Not good. Now I use a metal ruler that I can line up on my cutting board all the way across. It is a life saver. Lots more accurate than the first ruler. Hope this helps.

Starching (or using sizing) when ironing your fabric before cutting helps to make cutting more accurate, too.