How do add a chain to a mirror to hang?

You can affix it in the back with glue. E6000 might work.

Joan....You can hang the mirror and then hang the chain to give it the appearance of holding the mirror. I have done this in my bath with two mirrors but the mirrors are actually hung on a nail in the stud for stability then I added the hanger that looks like it is holding it.

does the mirror have solid wood or metal frame? Wood-get screw in hooks then add chain(you can add hooks to back of frame,sides of frame or top of frame depends how you prefer) find stud in wall to hang it from make sure that chain can support mirrors weight; metal attach hooks to mirror then add chain to mirror with J-B Weld 8276 KwikWeld Quick Setting Steel Reinforced Epoxy. then hang from wall studs. If you cannot find studs then you can use molly bolts to hang mirror on wall they are the strongest most secure for weight info. Sleeve-Type Hollow Wall Anchors... a.k.a. Molly Bolts

Molly bolts are a mechanically-interesting anchor. They combine the ease of installation of a plastic expansion anchor with much greater strength. The largest mollys can hold up to 50 lbs.Essentially, a molly bolt adds permanent screw threads to any material it is attached to. Thus, anything installed with a molly can be installed and taken down a number of times with no loss of strength. Viewing the graphic at the left, the topmost molly is designed to work with very thin materials. This style is typically used to add support to hollow doors for hanging towel bars, coat hooks and even "dummy" doorknobs.The second and third mollys are called "drive mollys", the second designed for 1/2" thick drywall and the third for 5/8" thick drywall. They both have a combination metal/plastic point that supposedly allows them to be driven into drywall with a hammer. Don't count on it! More later...The lowest molly in the graphic is an original-style molly... sans point! Mollys come in sizes from 1/8" to 1/4" (that's the screw size). As with most anchors, use the largest size that will work for the task at hand since the larger the molly, the greater the strength!To install a molly, first drill a hole the diameter of the molly in the desired location. Predrilling is important even with "drive mollys" since they can be bent or distorted if the wall is too hard. For smaller mollys, an awl can be used to form the hole as described for installing plastic expansion anchors (above).

Tap the molly into the hole until the head is flush with the drywall. Molly's have metal "teeth" that grip the drywall, and it is important these teeth are firmly embedded. Then turn the molly's screw clockwise. This pulls the base of the molly towards the inside of the wall while expanding the metal legs. A tip... though most molly screws have a combination Phillip's/slotted head, use a slotted screwdriver... the Phillips may slip and cause damage to the wall! Stop screwing when you feel strong resistance and the top of the molly has pulled tightly against the wall. The graphic (left) shows what you can't see... inside the wall.

How about the stick on hooks on the back I don’t know how heavy the mirror is