Is it going on a wall alone or over a buffet?

Guessing it is going alone. To be sure, you can always tape off the piece and get a feel for how it fits before pounding nails in the wall.

It will be on a wall alone without a buffet or table against it.

Se it at the standard 58-63" and see what you think. If it needs tweaking, do it then. Since my husband hangs my pictures, he holds them where I think they go, and I stand back and see if it looks right. The main thing about hanging a picture or anything is that it look right to you.

Thanks for the comments and the help. I held it at the standard height and it looks good. I just wasn't sure if the rule was different for a dining room. Like it had to be so high above the table or something like that.

The vertical center of the artwork is supposed to be hung around 65-70" (an average person's eye level). But there are many other factors involved. If you post photos, people can help you with more info.

https://www.etsy.com/shop/katshoa

You are so sweet, as we have all been there, worrying about the rules. Your eye will be your best friend with this project.