You will need a tool or Philips screw driver to start with. If you haven’t set up a board with bindings before you will no doubt wonder why so many holes in the snowboard. This allows you to adjust the width of your stance which is important for your balance and how you feel on the board. Start with the brand's recommended stance width and experiment as you go. You’ll quickly find out what works better for you and you’ll take an interest in getting to know your kit well.
Next up are the angles of the bindings. A good place to start is +18 degrees on your front foot, and minus 3 degrees on your rear foot. Again, experiment with the angles until you find what feels nice for you. Typically riders that focus on freestyle will have what is know as a duck stance, where the front and rear angles are almost mirrored. This makes riding in both directions feel the same. Riders that favour carving and freeriding will normally have more of an angle on the front, and less on the back. Make sure when you've found a good starting place that you tighten your screws up well. Not overly tight but you want to ensure that your bindings will not move.
Centred or set back? Freestyle riders will favour a centred stance for park riding. Freeriders may opt to place their reference stance slighty back from centre. Being closer to the tail of the board will allow your weight to keep the board afloat in deep powder. This is a good thing!