How to drywall in the vaulted ceiling bedroom plant shelf?

Question:I have a plant shelf in my bedroom at the peak of the vaulted ceiling. It is nothing but a dust and cobweb collector and of no real use. I don't have plants for this area and would rather have more wall space to hang art, etc. How do I go about framing the opening, especially at the angled ceiling to extend the drywall from the existing wall to the ceiling?

Answers:
hi
get a plumb line and place the point on the edge and used the string to find the location on the ceilling
mark it off and place 1x2 on the celling and on on the edge of the ledge the screw the drywall to it