Measure the wall in which you plan to frame and install your arched double doors. Measure the ceiling. Adjust your plans accordingly.
Choose lumber for your job. Make sure that it is either 2-by-4 inch or 2-by-6 inch wood.
Design your arch on a piece of plywood. Use a string as a compass to perfect the curvature. Cut the design out of the plywood.
Trace the plywood arch on the wall. Cut the archway out of the wall using a jigsaw.
Secure the arch using some metal strapping. Apply any stylistic embellishments (trim, finish, paint).
Hang the double doors in place. Fasten the doors with hinges.