2) Choosing Fabric

The challenge with limiting your quilt to using "just" the original fabric is that your fabric needs to have the right mix of colors, the right number of colors, and enough change in value to have interest. And all of this has to happen within one pattern repeat.

 Dave likes to describe the "perfect" candidate in a way that I don't personally agree with. He likes to say that you would have the right density of pattern and value change if the fabric you are looking at would look nice as a set of drapes. Or possibly as new cushions for the sofa.

 His point is that larger prints, with recognizable areas of background, tend to work well. The more dense the pattern, the more likely it is that almost every hexagon will have elements of every color in the fabric. In other words, they're all going to look th same.

 This is not necessarily bad, but you have to be ready to modify your quilt in other ways to deal with it. One way is to change the layout of the quilt (including the borders). See Green Koi as an example. Another way to deal with an overly dense pattern is to change the size of the triangles. See Undersea Garden.

 Many people recommend that you carry a pair of mirrors along with you when choosing your fabric. Most fabric/craft stores carry a setup that has two small mirrors taped together. You lay the fabric out, and stand the two mirrors up so they form roughly a 60 degree angle to each other. If you get it right, you can see what a hexagon would look like (sort of) if cut from this part of the fabric.

As you move the mirrors around, pay attention to the differences between all of the triangles you see. You're looking for changes. You don't really want them to all look alike. After a while it's simpler to just forget the mirrors and form a triangle with your thumbs and forefingers. Not quite as accurate, but easier than remembering to bring the mirrors.

 The main thing I like to try to remind people is that you're not going to have a lot of control over what the quilt looks like. How it "flows" has a lot to do with how many colors you have, and the ratio of those colors. Be sure, then, that you pick colors you like. If you like the colors, you can make it work. If you don't like them, you're stuck.

 Other things to keep in mind...

 Pattern repeat. You need six complete pattern repeats to get your hexagons. On a (roughly) 24inch repeat that's about 4 yards of fabric. If you use ALL of your triangles, with borders, you're going to get a large quilt. 1 foot repeat fabrics work well for a smaller quilt.

 Panel Fabrics: Cranberry Sprite is a good example of a panel fabric turned into a OBW quilt. As it turns out, you get a nice sized quilt using panels.

 Batik Fabrics: Be careful with batiks. Typically the pattern is stamped on, rather than printed on, the fabric. As such, it will be difficult, if not impossible, to get the patterns to align. Dave insists it's possible, and we actually have purchased some fabric, but we haven't tried it yet.