Girls melt before romantic surprises, right?! So, to conquer her heart, you shouldn't forget about it. In my turn, I would like to give you a cool idea of surprise for her!
Find an artist that usually paints people's pictures in the street. Arrange with him about painting your girlfriend's picture secretly for her and pay him beforehand. Then meet with your beloved, invite her to a cafe with large window. So, while you are sitting in the cafe, drinking and eating, the artist is painting the girl. It's better to sit down directly near the window.
Then the artist rolls up the picture, ties it with a ribbon, and goes to the place of his usual location. You with your girlfriend when walking, pass by this artist, unnoticeably he gives you the roll and you gift it to your sweetheart!
Just imagine her excitement and joy!!!