Anakin: Nothing; he thinks his love is more than enough. Thankfully, you agree.
Luke: Luke is classic: flowers and chocolate for Valentine's Day, your favorite candies for Halloween, wonderful gifts on Christmas, and a kiss on the nose to start off the New Year.
Poe: Poe has no idea what to get you for Valentine's Day, so he usually just takes you to another planet in his X-wing. On Halloween, the two of you stay in and keep each other company while watching old horror movies. By the time Christmas rolls around, he's already heard you drop numerous hints on what you might like. Poe always nails Christmas. Always.
Kylo Ren: Kylo believes it's the little things that make life special, so throughout the year, he leaves small gifts under your pillow, regardless of the current holiday.