Since we are into F&O expiry so till thursday technical resistance would work as per trendlines and technical indicators like RSI, MACD, Stochastics but support will work on global cues from Europe and USA.
Also there are many gaps created while falling downwards today a gap filled at 4944 now 4974 and then bigger gap from 5230 to 5330 till this are filled and nifty crosses over that global cues would be major support. Above 5350 closing for 3 days or weekly closing would confirm that 4800 was bottom but till then you have to trade with the trend.
FII in FO Index futures 490 Cr stock
futures 148 Cr index options 1170
Cr FII sell 100 Cr in cash and DII buy 300 CR
Nifty Hourly chart