Leotard, tights, ballet shoes.
For beginners/first day
Close-fitting stretchable top and stretchable pants (no longer than knee length pants) with socks.
Where to get attire
For shoes, leotards and tights, you can visit Costumes Connection located at Golden Landmark Hotel (opposite Raffles Hospital) near Bugis MRT
How to get there -- http://www.costumesconnection.com.sg/Contact_Us.html
For other good ballet shops to visit, Click Here