Another reason I always prewash....that V will haunt you for awhile as you learn. Fold the fabric and bounce it...let it tell you where center is.
I always open my first strip and make sure the V is not there before continuing on cutting my strips.

I always try to keep my pinky finger off the edge of the ruler to help stabilize it. Cut about 12 inches and then CAREFULLY move your hand up the ruler, leaving the rotary cutter blade IN the fabric and continue to cut. And Try to cut with the rotary blade at a 45 degree angle to the ruler, not tilted over and pushing against the ruler. ( you can have the handle at whatever angle is easiest for you to cut, just be sure the blade is straight.) Sometimes, we get to pushing so hard against the ruler ( it happened to me when my blade begins to get a little dull) that is moves our ruler.

Teeler - love your sense of humor.

I have also loved this thread. I have learned a lot from it. I do know one of my biggest problems is that I try to cut too fast - just impatient. I have read how others cut just a few inches and then move their hand up the ruler. So I guess my new resolution is to slow down and enjoy the journey and, hopefully, get straighter strips!

I was having a lot of trouble with my rulers slipping and I bought some of these, I put them on the bottom of my rulers and they work great. I even used the little centers and the parts in between on my smaller templates.
http://www.amazon.com/Grace-Company-TrueCut-Ruler-Grips-Transparent/dp/B003SBGW8C/ref=cm_rdp_product

They can be found cheaper! I think I found them at Joanns or one of those for under 4.00. I don't know why this is being underlined but please ignore that.

I have been using a 2x8' folding table for my cutting. But I have trouble cutting if i'm near the fold in the center of the table - so I moved my cutting mat to a smaller solid wood table with no folds and I get much cleaner cuts. On the folding table I would sometimes get skips because the table would flex in the middle. Don't know if this is clear as mud but. . . . . .

Good lighting can make a difference too. If your ruler is throwing a shadow (even a small one) your measurements can be off by 1/8" or more depending on the ruler.

The Quilters Slidelock made all the difference in the world in my cutting. I bought both sizes and I think its the best thing since sliced bread. We live close enough the the manufacturer I received them in two days!

It looks like you have a lot of good advice. It is good for us old times even to review and refresh ourselves on some cutting techniques.

I think it was mentioned earlier that your fold of the fabric should be at the bottom of your mat, close sort of to your belly. I usually fold my halved fabric another time, place the fold close, line up one of the lines with the bottom fold. It should run parallel to the fold, and then cut. We all seem to find many tips to help. The 1/4" cut check is a good tip.
I have also heard of folks getting PVC pipe cut long enough to bring your table up to the height you want. Put the legs(of the table) into the pipe, it should be stable and the right height for cutting.

I quickly read most of these threads and I have one moe suggestion. After you have cut 8 strips or so and your cutting using the WOF cutting method you might need to stop and realign your fabric.i know I often need to.