Twitter hashtags aggregate similar subjects on one page, so users can search for a particular trend, news, event, etc.
It is a free tool that can be used in combination with other forms of promoting services, products and events. Create a short, consistent and easy to remember hashtag so people can find and talk about your business.
You should have a banner that clearly show the hashtag people should use to refer to that specific subject.
See examples of pages that advertise their hashtags:
Figure: This Twitter widget shows the hashtags working
✅ Figure: Good example - SharePoint Conference 2014 banner to advertise the hashtag people should use