Reddit reviews Singer Sliding Buttonhole Foot

I think most of the one-step buttonhole feet will set you back $20+. But you can also use a [snap-on sliding foot] (http://www.amazon.com/Singer-Sliding-Buttonhole-Foot/dp/B008MNWMJY) or even a [slant shank open-toe buttonhole foot] (http://www.amazon.com/Slant-shank-Open-Buttonhole-Foot-11311/dp/B002F01QQU) The open toe foot will allow you to make manual buttonholes for much larger buttons than the one-step or sliding style.

I just had the same problem and unfortunately bought the wrong foot. Hopefully I can keep you from making the same mistake. If your machine does one step buttonholes, you need a foot with a slot in the back to place the button. This lets the machine know how big to make the buttonhole.

If you have a machine that does 4-step buttonholes you can use the cheaper feet like this one:
http://smile.amazon.com/gp/product/B008MNWMJY?keywords=Buttonhole%20foot&qid=1453646312&ref_=sr_1_3&sr=8-3

This is the new one I ordered for my machine that does one step buttonholes. It has not arrived yet but I'm hopeful it will work!
http://smile.amazon.com/gp/product/B00MNJIDDM?keywords=Buttonhole%20foot&psc=1&qid=1453646312&ref_=sr_1_18&sr=8-18-spons