First is most homes would be better served by larger art.
3x3, 4x4, or even larger. A great option for inexpensive big art is a large map or wall hanging.
Center of the artwork to be about 60 inches about the floor
More than one piece, like a gallery wall?
Space them just a couple inches apart.
Lay things out on the floor first to figure out arrangement.
if you're hanging art over furniture, the art should be about two thirds the width of the furniture.
Leave about eight to 10 inches between the bottom of the artwork and the top of the furniture.
If you don't know about the Golden Ratio, you are missing out.
It's basically a 60/40 rule.
Here's 6 ways to use it to design better homes and projects:
It helps you choose how much furniture goes in a room.
60% of the floor area should be furnished and 40% should be open.
More will feel cramped and less will feel underfurnished.
You can go really deep with this.
If a sofa takes up 60% of the seating in a room, accent chairs should make up the remaining 40%.
A coffee table should be 60% of the size of the sofa it serves.
On that coffee table, 40% should be decorated and 60% open.