Under spin questions

Okay, I've been seeing all of y'all's under spin ties. What are you doing exactly?? I don't have a mold, so is it possible to do it without one? I looked at a few pictures and it looks as if you just tie a barrel swivel onto the shank of the hook, put a ring on it, and attach the blade? What size swivels/rings/blades for a 1/8 ounce head would you guys use? I may be completely wrong on how y'all are tying them, but I'd love to give it a shot! Thanks!

Yep just put a Size 12 crane swivel on the shank and tie it down well, tie your jig and then use a 0/1 or 0 split ring and on an 1/8th oz size 1 blade.

Alrighty, I appreciate it!