Aside from the little robin I found on Etsy ($8) I framed things we already had like old family photos, my fashion illustrations, Will's artwork, and flea market finds. As for the frames, I used a mix of RIBBA frames from Ikea, vintage, or ones we had, and repainted them with gold leaf or glossy black paint. Some of the old frames didn't have glass so I took the measurements to a glass shop and had new pieces cut for around $5 each.
(Living Room Before)
I got the idea for the two leaf prints from Kate Spade's home. I simply cut out black cardstock and mounted it on Strathmore paper...
One of the many reasons I love a gallery wall is because you can switch things in and out so easily. Once you find a layout that works, the options are endless!!
A few sources for inspiration: