Are you wanting to cut angles with it?
Do you have a top slide made for your machine already?
If the answer is Yes to both questions, you loosen the screw on the bottom bracket and slide it into one of the T-slots. Then rotate it to the angle you want to cut. Use a protractor to figure the angle. Or if you already have a piece that is cut to the angle you want to cut, chuck it up in the headstock and line the edge of the top slide to the angle and then put your bit in the proper way to cut the piece.