Pantry Supplies: Scissors, sewing machine, jewelry pliers.
With the pliers, begin by studding the collar in whatever pattern you choose. Next, cut out the base of the collar. I cut mine three buttons down. You'll want the length to hit mid chest. Lastly, hem the edges of the collar so as not to fray. If you don't have a sewing machine, you can skip the last step if you find a top that's a non fray fabric.
This collar accessory is ideal for tops that are more form fitting. With the collar, you can avoid having too much bulk under your top and more room to move around. I'm definitely going to be using this in the summertime under some short sleeve shirts and tank tops. Yes, I'm dreaming of summer already. Whoops.