well, if you see one that catch your fancy on the website, better if she is a girl with an address. First of all, if you go, you have a possibility to leave when she opens the door. If she is not what you are looking for, you can always say nicely "sorry". Don't be rude, smile and leave. Other advantage, usually, more than one girl works in the same building (the word cluster is used for a good reason), so you can try your chance at an other door and repeat the same process if the girl is not what you are looking for...
Very often, they do not speak english, but your reason to come is quite obvious. If you do not speak cantonese nor mandarin, it might be hard. So, learn at least the number:
yat ba: 100
yi ba: 200
sam ba: 300
sei ba: 400
mm ba: 500
luk ba: 600
tsat ba: 700
bak ba: 800
gao ba: 900
these are just the pronunciation of cantonese numbers, not taking the tones into consideration, but usually, the context will help you.
hope it will help and have fun!
