I built the base out of pine 2×4s. I glued up three boards for the legs. I used a longer board in the middle to create a tenon which saved a lot of time by not having to cut the tenons out by hand.
Next, I chopped out the mortises in the legs for the stretchers using a chisel.
Then I cut the tenons on the stretchers. I used a small backsaw to cut down the cheeks and split the waste out down to the cheeks with a chisel. The process went much faster by chopping out the waste rather than sawing it out.
I then dry fit all the pieces together and, while some of the joints are a little loose, I think it turned out pretty good for the first mortise and tenons I’ve ever done.