I have had nearly 20 years experience of creating and maintaining a 1/4 mile gravel drive. I'm in the process of concreting it now, but due to the huge expense of doing so, I still have gravel most of the way. /forums/images/graemlins/blush.gif
I can't tell you if my method is best or not, but it is through trial and error. I do have a very smooth and flat driveway none the less.
I have a rear blade, a FEL, and a 6' box scraper. By far, the box scraper is the preferred tool to create and maintain a gravel driveway. About every two or three years, I have to use the box scraper to pull the gravel back in from the sides from where it has been scattered out. I then grade those back into the driveway.
When I started the driveway, I first scraped off all of the grass and sod that was present. Doing so also began the levelling process. I then laid down about 3 inches of #2 gravel. This is roughly golf ball sized gravel. That was followed up by about 4 inches of #5's. This gave me a firm bed. A few months later I put down about 4 inches of #53's. This is the same as the 5's, but the 53's have lime mixed in. The 53's pack in well and seal up the surface fairly well. Skip ahead several years (and several tri axle loads of 53's for maintenance) and I now have been using #9's. The 9's are smaller and make for a smoother surface.