the chinese Balentine's day called "Qi Xi" it s come from a romantic story .
and i think we dont do some specific things ,
just enjoy with your BF/GF at that day , it is nice enough. i guess
it s can not say modern to describe chinese Valentine's
no specific gift flowers (Roses) maybe ....
you can do what you want
Option one: book a nice hotel room, small gift, dinner out in a cosy restaurant,make love and cuddle...
Option two: go to supermarket together, small gift, cook together or you cook for herat home, drink wine with candles, then drunken sex and sleep..
Roses? No. trouble to carry and price is getting higher now...