First and foremost you should have a trading and demat account for this purpose. You can approach a reliable company which offers these services. I am having account with Angel Broking. Even ICICI provides a wonderful service. After that you can ask them for any help regarding Stock Marketing.
To purchase/sell shares, you require the assistance of a stock agent. Specialists are enlisted with SEBI who is the capital market controller in India. You should be comfortable with ICICI Direct, IndiaBulls, Sharekhan, etc.
