Call her the next day.

Always laugh at her jokes.

Tell her (truthfully) that you can't wait to see her again

Call her just to say you were thinking about her.

Bring her a teddy bear and chicken soup when she's sick.

Bring her flowers for no reason.

Send her a (handwritten) letter just to say hello.

Always remember your anniversaries and bring her something sweet

Take her for a walk at sunset and stay to look up at the stars.

Surprise her with a candle light dinner.

Never stop trying to impress her.

Never forget how much she means to you