Wow, Nikki you are lucky - high ceilings are incredibly sought after! I would recommend highlighting this design feature by installing your art in groupings. In the attached image, you can see how the homeowner used their art to draw the eye up, really highlighting the high ceilings. A great way to plan your layout is to cut craft paper to the sizes of the pieces you will be working with and arrange them either on the wall with tape or on the floor until you have a grouping you like. Once you have predetermined your arrangements you can mark on the wall where the pieces should be hung and - voila! - you have created an instant statement!

The arrangement suggested by loom decor works fine--if you are using fewer and larger pieces then as a general rule hang the center of the artwork at eye lever --about 5'-6" above the floor.
PyramidDG.com

Keep art below door and window frame height. That is where you and the furniture live. Pieces over furniture about 5" above it and free hanging pieces and groupings with the center point at 60" above the floor. Unless you have a huge piece which requires a huge wall, hang art where you live.

Art is typicallly hung at eye level. Start there then go up just a bit. You don't want to give your self a stiff neck looking up

Thanks everyone. I'll give it a go. I love the grouped art idea especially. Thanks

The ceiling in this room goes up to the second floor, 18'. art was hung at eye level to ground the room.

It depends on what you're hanging. A Large piece or a few pieces salon style?

I agree Jill. If you have a large single piece, you can start low and reach high. Do you know what you are hanging, or are you trying to figure out what to buy?