The ruffler foot is a great tool if you want to sew ruffles and not gather thread. This works great, but the ruffler foot has some issues coming out of the box.
For one, it is very tight. The video contains some tips on loosening it up, attaching with the proper tool, adjustments, and sliding in fabric past the teeth.
Don’t forget: SEW. FAIL. REPEAT.
Check out http://DadSews.com for more videos.