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.
