Be yourself. Be nice but don't go the extra mile to please her because most guys make the mistake of doing lots for the girl they like and cannot keep up with it when they actually enter a relationship. This gives the impression that the guy no longer love them as much or is starting to take them for granted leading to unnecessary quarrels.
However, please be mindful of her feelings etc. Watch her body language to see if she is comfortable with the conversation or is she getting bored with you etc. Stick to safe topics like hobbies, sports, movies, tv programmes, books. holidays, weather etc and not on things which can get heated like politics and religion unless she brings it up.
Be dressed neatly dress and stick to smart casuals since those are suitable for most places in Singapore and you'll likely be comfortable in them too. If you wanna use colonge, don't drench yourself. Just make sure that you are neat and presentable with no weird BOs

If you want to get her something, get her a stalk of rose like maybe a blue rose. Bouquet is a little too cliche. Of course if you can make something, that is even better.
Anyway, just remember don't go on and on about yourself.