There is a lot of freedom here. But we highly recommend dressing in a manner displaying respect for your host culture.

At Project Mehrauli, we seek to show respect to the locals both in action and word. So with Mehrauli leaning more conservative in dress compared to the broader Delhi, we seek to honor them by recommending our guests to wear more modest attire.
So what is does this entail? For everyone, this means pants (or long dress for women) and sleeved shirts. And for women, we encourage wearing a duppata, a large scarf which can be used as a head covering when entering religious sites. Occasionally men too will want to cover their heads. At gurudwaras (place of worship for Sikhs), men can use provided cloth for such a covering.
In addition to the modest clothing, we encourage wearing easily removable shoes and comfortable clothing. On many of our tours and experiences, you will be often taking off your shoes, between visiting a religious site or an Indian home.
Also depending on the weather, you will want to dress according to the temperature. Summers can get fairly spicy temperature wise, so you will want some light and breathable clothing then.
Showing these simple forms of respect can be the connecting point between you and a local. We are passionate about making travel more personal, connecting people with people not just places. So wherever you go in India, we hope this advice will serve you well!