The Instagram series prints are designed to be ready to frame without any matting using readily available, standard size frames.
Out of the packaging straight into the frame.
Different frames for different images.
Nice. Where do I get the frames?
The examples above are all inexpensive ready-made frames. The large ones are for 8.5x11, and the smaller ones 5x7. These are from Aaron Brothers, but these standard sizes should be generally available.