Cut to length and rough width. Total frame size is 26"x22" the boards are 1 1/2" wide and about 3/4" thick

Miter to 45 degrees

Lay it out, make sure your miters line up. If not, now is the time to tweak it

I set up my router table so it's about 1/2" wide and 1/4" deep with a straight bit. You can modify as you see need to fit in your picture. 

Turn the outer edge of the frame, tilt your table saw to 15 degrees and set your fence 1/2" from the blade. This will ease the edges and keep the frame from being so chunky. 

Now it's time to glue. I use tape to hold it all together. Sometimes I'll use clamps as well, but I have luck with just tape as long as I'm careful to hold it steady and TIGHT. 

Also, measure diagonally to make sure it's square. 

Here it is all glued up. I didn't take any pics of sanding or applying danish oil, but I figure you know how to do that

Find center and nail on the sawtooth hanger thingy. 

I just taped in the pics. I know, the proper method would be to nail tabs to the back, but to be honest, my wife had a hard week at work and I was in a hurry to get them on the wall. 

Also note I did not use splines in the corners of these frames. The pictures are mounted to chloroplast and there is no glass, so it's really light. If I ever add glass, it will be easy to add splines later to beef them up.