which one is on top?

[Zinnia.]

left thumb goes on top. arms and legs switch but generally right goes on top.

 

[BungoTheElf]

1. when you clasp your hands, which thumb is on top?
left thumb!
2. when you cross your arms, which arm is on top?
left arm!
3. when you cross your legs, which leg is on top?
left leg!

not sure why it's all my left limbs but if I switch it over it feels kinda weird