I love ruler work. I love the look it gives my quilting. The precise nature gives a very professional appearance. Even a little ruler work added in to other quilting, really makes a statement. Here is a photo of just a little ruler work and lots of fill work.
It can be a little learning curve using rulers. For me the biggest issue was control. Which brings me to the point of this tip.
I use these ruler grips called True Grips., on the bottom of my rulers. (Yes, we carry them in our store.)They give me great control of the ruler without using a death grip, and are so small I can still see through the ruler where I need to. I can still easily move the ruler when I need to. And the adhesive sticks very well, yet I can get them off if I need to.
I like to place them close enough that there is one under my hand no matter where I place my hand on the ruler. I also think about where to place them so they do not obstruct my view of crucial markings on the ruler.