A few people have asked how I cut my fabric and when I tell them I use my ruler measurements and lines and pay little attention to the markings on the cutting mat they get confused. I teach this method in my classes and decided I'd share it here as well. 
When quilters are ready to use a piece of fabric to start making a quilt we start with a straight line of fabric. If we don't none of our cuts will be straight and our quilts will not come together as they should. To get this first straight cut there are a couple of ways to make that edge straight.  Here is how I do it. 
1  1) Take the fabric so the selvedge edges meet at one end and there is a fold at the other.  Fabric comes that way when cut from the bolt, but you may be using a piece that no longer has that fold.  Make the fabric as flat as possible with no wrinkles. Press it if needed.
 1) Lining up fabric
   2) Lay your fabric with the fold even with the bottom line on your cutting mat as indicated in this photo. Line it up with a measurement on the cutting mat. In this photo it is at the 4" mark. 
   Notice how uneven the cut edge is here in the photo.
 2) Lining up ruler on mat 3)Place your ruler (template) so that you have a line on the ruler, or the edge of it, even with the line where you have your fabric
       3) Lining up other edge with line on the mat 4)Make sure your ruler lines up with the same line (mark) on the selvedge edge as it does on the folded edge. (Notice again here it is at the 4" mark). Don’t worry where the fabric shows under the ruler as that is the uneven end.
   IMGP7046 5)Using your rotary cutter placed against the ruler, and holding the ruler down firmly slowly make your cut along the ruler. Carefully hold the ruler as you cut so it does not slip off the place you need your cut.
  6)  Once you have this first cut your fabric is ready to use with that straight line to start cutting your quilt pieces and you can use the ruler markings instead of the markings and measurements on the cutting mat for the rest of the cut.  For me it makes cutting my pieces easier. (Some quilters will continue to use the measurements and markings on the cutting mat and that is fine. Like quilters will tell you - there are no quilt police!) I do still use the cutting mat measurements from time to time to re align my fabric or to cut a piece that is wider than any of my rulers. 
  4) Ruler lines vs cutting mat
   7)  SO to cut using the measurements and markings on the ruler instead of the cutting mat…..
Notice my fabric is so NOT lined up with the measurement markings on the cutting mat. This is what makes this so much fun!  I don’t have to worry about how my fabric lays on the cutting mat.  (I know some quilters are gasping at the moment…)
Place your ruler so the measurements on your RULER line up with the straight edges of the fabric at the fold as well as the edge you just cut. Line the ruler up along the entire edge of left edge of the fabric.
 5) Fabric lined up under ruler while cutting8) Once you have it all lined up and even, use your rotary cutter along the right edge of the ruler and while holding the ruler firmly down, but your fabric.
   IMGP7054 9)To make your cuts smaller or using a square template you can also just line the ruler up with the fabric instead of lining your fabric up along the measurements on the cutting mat.  This comes in handy when you can’t see all the measurements on the cutting mat. 
EXTRA  TIP:  Once you start using one ruler/template continue to use the same one, or one by the same company throughout the entire cutting process of that project. Each company uses different line markings which may be wider than another company. If your cuts are just a tiny bit off on each and every cut eventually your pieces are not going to be the same size and will not fit the way they need to.   I hope this has helped some who were confused about being able to cut without using the markings on a cutting mat.  If you still have questions, contact me and I’ll do my best to help.