I don’t know about you, but my mother taught me to never bump a loaf of bread when it had risen. She showed me how to ever so gently slide the loaf into the oven and ever so gently close the oven door. Any slamming around and the loaf would collapse in upon itself.
But not so with sourdough. (Ha---that rhymes!) Once the dough is all big and poofy, then you get to do some major playing around, flipping it over, pushing it from the board to the oven tile, and even cutting, or docking, the boule. This turns bread-baking from a domesticated, genteel activity into a therapy session for the rebellious and defiant child. Not that I harbor any resentment toward my mother and all the many many instructions she gave me. No, no, certainly not. Though slashing that soft, risen dough does sooth my soul....
Of course you must still be gentle—no poking or pinching, though that is a tempting proposition since the dough feels just like a baby’s butt, or a baby’s marshmallow cheeks (facial ones).
First, dump the loaf out upside down on a bread board (or in my case, a cutting board).
Second, dock it. There are all different cuts, depending on which type of bread you are making. You can create your own cuts, of course—the only goal is to be consistent so that a certain cut always indicates a certain type of bread. I use a razor to dock my bread because the cutting device needs to be, um, razor sharp. Make the cut quickly—a ½ inch deep cut at a 45 degree angle.
Docking the bread is not simply for decoration—it allows the bread to expand properly. If you didn’t dock it, the boule would explode out in one way or another. By cutting the boule, you are telling it where to expand so it does it in an attractive fashion.
I feel powerful and bossy when I slash the dough and then shove it into the oven. The dough collapses quite a bit (maybe I'm too bossy?), but within the first five minutes of being in the hot oven, it rises back to it’s beautiful shape, and then even grows some more.