Refrigerate the dough until use. Freeze if not using within 2 days.

What you need:
1.  Something to bake on: a baking sheet.
2.  Croissant dough.

1. Shaping:  Roll to 1/4" to 1/2" thickness, dough should remain cool during rolling.  You can make standard croissants using triangles cut with a 2" base.
2. Proofing:  Once you've shaped your croissants, arrange them on a parchment on a cooking sheet with about 2" of space around them, they'll grow during proofing.  Put two racks in the oven.  Bring a saucepan with water to a simmer and place it on the lower rack.  Place your croissant sheet on the upper rack. Let them sit for 1-2hrs.  Alternatively, you can just turn on your oven light, and let them sit in the oven for around an hour, depends how picky you are ;)
3. Eggwash:  Mix one egg yolk and a spoonful of milk or cream.  The croissants should be puffy now, carefully brush them with the wash.
4. Cooking:  Finally! Haha..  Preheat the oven to 425 degrees.  Bake for 18-20 min.
5. Yum.