In general, artwork should be hung so that the centre point of the picture is at eye level for the average person. While this won't be possible in every situation, it's a good guideline to keep in mind. Remember a grouping of pictures should be thought of as one unit.
Test an arrangement of pictures by laying everything out on a large table (or on the floor), playing with combinations until you hit upon one that works. Cut paper the same size and mark where the hanging screws are. Then tape the paper shapes to the wall and you will be able to see where to fix the hooks.
create an art shelf
Art shelves are a great way to add interest and take up very little space. Artwork can be hung on the wall over the shelf as well as set onto the shelf with other decorative objects. Opposite pictures shows two art shelves with just framed art, easy to do and it looks great.
pair up frames
Why not mix and match art with the same frames. Be creative.
colour and size
Match or contrast for your room scheme. Choose artwork that underscores the mood or theme of your room. Is the room vibrant, pastel, or neutral? Is your furniture casual, formal, modern, or traditional? These are clues that will help zero in on the type of artwork that compliments the colour and scale of a room. Vibrant colors bring excitement to a room while neutral colors are more calming.
bigger is often better
One large painting or framed print makes a statement and keeps things simple. It can also call attention to the focal point of the room which is often the fireplace.
Strong horizontal lines in artwork, or in the way artwork is framed or hung, tend to be calming and can give the illusion of width in a narrow room.
The arrangement (shown far left) is made even more dramatic by hanging the prints next to each other or one above the other, furthering the sense of height.