Stretch measuring tape at a 90-degree angle from the center of one of the hip rafters down to a ceiling joist in the attic. Cut a piece of 2-by-6 lumber to that length.
Screw the ends of the cut 2-by-6 lumber to the rafter and the ceiling joist using 4-inch long screws.
Repeat Steps 1 and 2 for the other three hip rafters in the roof.
Attach a metal band to the side of a ceiling joist at the eaves where the joist meets a rafter by screwing two 2-inch-long screws through the metal band and into the joist.
Wrap the band up and around the rafter and screw the other end of the band to the other side of the ceiling joist with two 2-inch-long screws.
Repeat Steps 4 and 5 for the rest of the ceiling joists where the bases of the rafters meet the ends of the ceiling joists.