Not many days of the year do men get such an easy lay-up of what to do to make spouses or girlfriends happy.
Cards, flowers, candy, dinner for two at either a restaurant or something you made....
Some nice words and "BINGO" you did the right thing out of a laundry list of doing the wrong thing....
And if she is given the opportunity to "flex" or show off what you did for her to her friends....you just scored a jackpot of good will from her.
Walmart flowers at her house/apartment....buzzz..loser.......flowers delivered to her office....ding ding ding.....winner.
Red roses.....normal and expected....pick her favorite color of roses....white, peach, blue, or even black.....winner again.
All that is required is for you to actually think about what she usually likes....and something she can show off to her friends. (Lingerie is not something she should share....and if she does....you got bigger problems)