1) red string of fate leads you to your soulmate

2) a timer is printed on your wrist ticking down to the exact time you meet your soulmate.

3) Anything you write on your skin also gets written down on your soulmates (and vice versa)

4) Your soulmates favorite flowers start growing on your arms and legs, the start to glow when in the presence of your soulmate. And if they are killed by exterminators the flowers wither and die.