How do you replace a window with a bay window style?

I'm tryng to replace my old window attached to my kitchen sink with 5'x3' baywindow. I need to know the basic steps on how to layout the framing, what's the process of isntallation.How do you replace a window with a bay window style?After the removal of the unit you need to reframe the rough opening if the unit is a different size. If not you should check the condition of the framing members that are in the wall already. If you do resize the opening I would reccomend a double jack stud as well as a double window will. If you are going to replace your header then I would use LVL material, same size, greater strength. Next you need to apply what we on Long Island call %26quot;visqueen%26quot; but the rest of the world calls poly. This goes on the sill first and then the jack studs. It creates a water barrier. Next install the new window using the cable support system that should be included with the unit. Use silicone at all nail flanges to ensure it is watertight. i would also recommend using a Tyvek of Vycor window flashing system around the unit...it is a little pricy but well worth it. Reside around the unit and you are done outside. Stuff insulation in all new openings, install the head and seat boards, patch all the sheetrock and install the casing. GOOD LUCK