I wanted to make some Seahawks Green and Blue earrings for my wife, daughter and granddaughters for watching the games. None of the designs I found worked very well, the LED's came loose or pointed in odd directions. I designed an LED/coin battery holder to hold both pieces in place and attach to an earring blank. Uses a CR1220 coin battery.
Glue holder to either clamshell or pierced earring blank. Insert LED from the bottom and then insert the CR1220 battery to make the LED light.