There are some ways to promote business online.
Use the Local Listing Services A local business listing is an online entry that contains your business Name, Address and phone number along with other business details. There are a lot of websites like Tradejinni, Justdial and Yellow Pages where local businesses you can create free local business listings. Registering your business on Business listing sites allows it to be found more easily on Google searches and it shows up on Google Maps.
Social Media A good strategy is to be available on the main Social Media stages (Facebook, Twitter, Pinterest, Google+, Instagram and YouTube), however, you should to pick ONE stage as your principle Social Media stage and truly figure out how to utilize it professionally and post on it consistently. Make sure the platform you decide to use as your main one is also used by the majority of your target market.