I am not primarily a baker. I'm much more into the non-dessert, non-bread aspect of cooking, but I do bake sometimes (especially pizza crust and flatbreads). Other people who are much better at baking than I am (including Shauna over at http://glutenfreegirl.com/) have found that gluten free baked goods come out much better if you measure flours by weight rather than volume. This also makes it easier to substitute one flour for another, because they can have quite different densities.
Weighing things may seem really sciencey and intimidating, but it doesn't have to be. I find it easier to do because you can just stick your mixing bowl on the scale and zero it each time you start adding a new flour, and you don't have to bother with measuring cups and sifters. I strongly recommend that you bake by weight, and all of my recipes for baked goods will include weights. You don't need some sort of fancy high tech scale either. I bought mine at Canadian Tire for $10, and as an added bonus I can also use it split skeins of sock yarn in half by weight, so it's a multipurpose piece of equipment.
However, I know that some of you will absolutely refuse to bake by weight. I will try to also include approximate volume measurements, but if I ever don't, this is an approximate conversion you can use:
140 grams = 1 cup
105 grams = 3/4 cup
70 grams = 1/2 cup
35 grams = 1/4 cup
Hopefully you can interpolate a bit from there. This will also help you convert regular wheat flour recipes to gluten free recipes if you're really into baking. Just use 140 grams of gluten free flours for every 1 cup of white flour a recipe calls for. I really want to emphasize, though, that your will get much better and more consistent results with your baked goods if you bake by weight.
