i will be staying in a hotel near guangzhou east railway station so i would like to know rom where and which number of bus should i take to reach baima market because taxi is very costly.

From the East Railway Station, you can take the subway line 3 to reach Zhujiang New Town Station where you can change to line 5 to reach the Railway Station.
Upon reaching the Railway Station, get out of the station from Exit G and then you can see the Baima Clothes Market.
Yes, the market is open on weekends.