Hi Lakshman, you need to advertise through different media including online (property portals like 99acres.com) and offline magazines and newspaper (classified sections and specific real estate supplements).
The online media is faster and quicker. You may also buy a paid package offered by online portals. They charge on a monthly basis and in return, give your ad prominence over non-paid ads. For paid packages by 99acres.com, you may visit this link: http://www.99acres.com/do/buyourservices