All you need is to take a public transportation and a little bit of walking.
Asia Jaya LRT station - 5 mins walk
Any buses that can get to Asia Jaya station
KL Sentral station (KTM/LRT/Monorail)
Any buses that can get to KL Sentral station
ps: Bring your own umbrella.
ps again: Not sure about driving though, will it be very jam? What time is the best to avoid the jam?