Determine any preparatory steps needed before framing. If your painting is on an unstretched canvas, stretch the piece to a wooden stretcher frame.
Measure the dimensions of the finished oil painting. Using a rule or tape, measure the back of the painting from the edge to edge both vertically and horizontally. Jot down these measurements.
Remove any cardboard backing or glass from store-bought frames. If you purchased a custom size frame follow any included instructions for preparing the frame before inserting the painting.
Put your painting in the back of the frame, securing it with offset clips. Place one clip on either side of the frame and screw it into place using appropriate size screws for the frame size.
Remove any sawtooth hangers that may have been pre-installed on the back of the frame. Typically, these are not very sturdy.
Insert appropriately sized screws, one approximately one third from each end of the top of the frame. Do not tighten these screws all the way; leave a bit of space for the strap hangers to rotate freely
Slip one end of hanging wire onto each of the frame screws and wrap securely (six times or so). Leave a little slack in the wire to make it easier to hang. Test to make sure the wire is strong enough to hold the painting.