Assuming you have a bow press and a proper size string, it wouldn' t be hard at all. One thing that I would do however, since this is your first time would be to freehand draw, or mark on the cam itself with a pencil as to wear each piece connect. For an experienced person, it may seem trivial, but to a new comer, it may seem a little complicated. Another suggestion would be to mark on the cam (cams), where the cam is in relation to the limbs (it would be a straight line drawn on the cam with the limbs being the template). You will want the cam to be in the proper position when it is finished, and you may have to twist the string, cable, or both to achieve this.

Good luck.