Ashton- You got "forever" on the palm side of your ring finger and Ashton got "always" on his.
Luke- Luke got a Yin on his right wrist and you got a Yang on your left wrist.
Calum- You got a puzzle piece on the inside of your right arm and he got a puzzle piece on his left. When you held hands it would look like they were connected.
Michael- You got a sun on your ankle and he got a moon on his.