Gather the dough on the floured board and knead it for a few seconds ( no need to develop any gluten), form into a disk, wrap in plastic and set in the fridge while you work on the butter.
Place the butter square inside the dough square and fold like over each corner. Make sure the seams are sealed.
You will have a nice little package.
Roll out the dough with the butter inside to a rectangle approximately 9 by 17 and tri-fold like a letter.
This is the first "turn". Now you will need to do a minimum of 6 turns for flaky galette dough or many more if you are looking for a croissant type results.
At this point I like to let the dough rest overnight in the fridge wrapped in plastic. The next day, take it out and split into two even pieces. It will make your life a little easier when trying to roll it thin. Roll each piece out to about a 9 by 17 rectangles and tri-fold again, and again, and again.... do you feel those arms burn yet?
You can get 3 to 4 turns on each piece of dough before it becomes too warm. You will need to work quickly though. If you feeling that the dough begins to stretch, rather than roll and starts sticking to the bard or the rolling pin, it is getting too warm. Fold it, wrap it in plastic and let it rest in the fridge for at least 30 min or better yet, a few hours.