YOU CANNOT “FOLLOW” A HASHTAG DIRECTLY THROUGH YOUR TWITTER ACCOUNT. This is generally a confusing point for those of you who are new to Twitter and hashtags (#). A hashtag is not a source of tweets; it is simply a way of labelling or tagging tweets so they can be easily pulled together as a group. Hashtagging is the mechanism used for trending.
TWITTER SEARCH: An easy way to track hashtags is through your web browser or twitter App: go to Twitter Search. Search for a hashtag you want to track. Include the “#” in your search query, for example #MSBlog. Keep the page open in your browser and refresh it to see the latest results.