Have the Frame Made
Spread the craft paper over the work surface, and lay the oval mirror on top. Center the mirror onto the paper so that there is enough paper on all sides to work with.
Trace the outline of the oval mirror onto the craft paper. Hold the mirror steadily in place, and guide the pencil around the edge of the mirror. Position the pencil point as close to the mirror as possible, and trace the mirror all the way around until you reach the starting point.
Carefully slide the paper out from under the mirror. Avoid breaking the mirror--do not lift the mirror too much or pull the paper too fast.
Cut out the outline of the oval mirror from the craft paper. This is the pattern of the mirror that you will give to the professional framers to custom make a frame for your mirror.
Set the Oval Mirror in Its Frame
Dry fit the oval mirror into the frame before permanently setting it with the silicone adhesive and tacks. With the help of another person, lift the mirror, turn it over and fit one of its narrow ends into the top of the frame. Carefully lower the other end of the mirror into the frame. Remove the mirror after checking its fit.
Apply a thin bead of clear silicone adhesive into the frame's groove.
Position the oval mirror into the frame. Lift the entire mirror over the frame with help, line it up and lower one narrow end into the top or bottom of the frame. Slowly lower the opposite end of the mirror into the frame, and gently press it down into the adhesive.
Close the tacks down over the mirror. Use a flathead screwdriver to fold down the tacks over the edges of the mirror. Take your time and do not scrape the mirror in the process.
Screw the mirror brackets into the frame, with a drill and around the mirror, if these are used instead of tacks to secure the mirror.
Cover the back of the mirror with craft paper or a thin piece of foam or wood backing to cushion the mirror. Adhere it to the mirror frame with double-sided tape around the edges, and cut the excess away with a utility knife along the outline of the mirror.