Using a double crust recipe, divide the dough for the top & bottom crust. You'll need about 1 ½ inch of overhang. My pie crust recipe is enough to make a 9x13 slap pie (double crust). If you're using a round pie recipe, you'll likely need to measure up to make more dough if you want to make a slab style - or if purchasing, you'll likely need 3 round disks.
Roll the bottom crust and fit it into your pie plate allowing for the overhang. Chill.
Roll the top crust and either chill it whole (rolled out) or cut it into 1 ½" lattice slices to create a rustic lattice top.
Fill the chilled bottom crust with the blueberries, easing them into the gaps and edges.
Lay on the top crust (if you're using the whole crust as a sheet) lightly pressing the edges. If you're doing a lattice application, take a look at the demo video to watch how that's done. Trim off the rough extra shaggy overhang (leaving at least 1 to 1 ½ inches to work with). Then pinch together. Roll the edge over onto itself to make a 'double-edge'. Next flute the edge or your desired design. If you're not doing the lattice top, then slash a few holes to allow steam to vent. Chill again - at least 10 minutes.
Add water to egg yolk, beat. Brush this on the chilled pie which will create a golden color. Sprinkle with turbinado or white sugar. (optional)
Bake in a pre-heated oven at 425f for 15 minutes, then lower the temp to 375f and bake until done. About 30 more minutes, possibly more depending on how large your pie is. Tent with foil to prevent over-browning.
I bake my pies on a sheet tray lined with parchment paper (to catch any drips). In my oven, I also have a baking steel and I bake the pie on top of that. It will give the bottom crust additional even heating, creating a nice firm, but tender crust. No more soggy crusts!