First you have to reveal your skin type. Singapore is is a warm and humid country so if you have oily skin, you need something with oil control. If your skin is dry, get a moisturizer.
I am hesitant to recommend most beauty parlours because a great number of them are aggressive in sales tactics.
Based on my past experiences though, you might want to drop in at:
http://kiray.com.sg/spa.asp
I found the staff friendly, atmosphere very comfortable, and products reliable (from Europe, no dodgy brands).
Hope this helps!