Add to the starter all of the dough ingredients -- start with the smaller amount of flour -- and mix. Should make a smooth, supple dough. If too wet, add up to 60 grams more of the flour.
Lightly grease a bowl and add dough. Cover with plastic and let rest for 1½-2 hours. Shouldn't be doubled in size but close.
A couple of ways to form this -- three strand or four strand is all I've done. Whichever one you decide on, deflate the dough, weigh it, and split it into X equal pieces and roll out to a 20" log and let rest -- will probably relax back to about 18". See notes below about forming. Or check out any of about 4-million videos on YouTube about it.
Make the glaze.
After you've formed your braid and put it back onto a parchment-lined baking sheet, brush with the glaze, cover with lightly oiled plastic wrap, and let rest for 45 to 60 minutes until doubled.
Preheat oven to 375°F
Brush with the glaze again and bake for 35-45 minutes until a deep, shiny brown. If browning too much, tent with foil about half way through. An instant-read thermometer should register 195°F+.
Cool on a wire rack for at least an hour before slicing into.