While traveling inside Delhi, opt for prepaid taxis and autos where available or else bargain hard.
The Delhi Government official website www.delhigovt.nic.in has an auto/taxi fare calculator. This might be a helpful resource before you decide to venture out.
Carry lots of suntan lotion, if you decide to venture out in the sun be it the summer season or the winter season in Delhi.
If visiting the Jama Masjid, take care to dress respectfully. Do not wear shorts, mini-skirts etc. Robes are also available for hire at the northern gate.
Most of the stalls at Dilli Haat do not accept credit cards, so be sure to carry enough cash.
When traveling from one place to the next factor in an additional 30 minutes to an hour for battling the traffic on the streets.