I Love You Handshake
When you grip someone's hand so hard you're trying to make them feel your love. It looks like your fingers are doing a weird wave, and it's usually followed by a stupid smile that makes you look like an idiot.
My girlfriend and I did it in the park. The dog looked confused.
My friend and his crush did it in the hallway. It was like they were trying to make the whole school watch.
My uncle and aunt did it at my wedding. It was the most embarrassing thing ever.