Cover a solid, flat surface with a piece of cardboard, and place the picture frame or floater frame moulding face down on top of it in the correct order. Avoid placing the frame on carpeting or a similar, rough surface as it could scratch the frame.

Each side of the picture frame has one or more dovetail openings routed into each corner that are only visible from the back of the frame. This is where the dovetail keys will be inserted, joining the corners.

Note that some frames may have more than one dovetail key per corner. If this is the case, start with the tallest key on the outside of frame moulding and work towards the shorter keys on the inside of the frame.

Apply a small amount of wood glue to the two sides you will join. Line up the sides carefully and press them together.

First, insert the key by hand, with the rounded end of the dovetail key entering first. When you have pushed it in as much as possible by hand, ensure the key is flush with the frame by gently tapping it with a small hammer. A large hammer will increase the risk of chipping the wood.

Once you reach the third and fourth corners, apply glue to both corners at the same time. Note that it may be more difficult to apply glue to the final corner due to the smaller opening.

Let the frame dry for approximately 30 minutes. Once dry, a permanent, strong and reliable joint is created to ensure the picture frame stays together.