I used this tutorial for making the shorts. The directions are straight forward and simple.
And for the suspenders these directions sewed up in a jiffy. The fold over elastic makes them comfortable and easily adaptable for fit. And now the elastic comes in a wide variety of colors and prints.
The directions say to stitch a diamond shape to secure the two straps together. I didn't do that. This little guy lives away from me and I couldn't size them on him. By not sewing the straps together and leaving them separate, they can be adjusted for fit...plus they can grow with him.