Hashtags are a free discovery tool on Twitter. People are checking the trending hashtags all the time, and your tweets are more likely to be seen, if you’re tweeting about something that’s trending. You can also change the location of the trending topics list. I check many places, and mostly pick topics that are somehow related to music.
When you tweet something interesting about a hot topic, your profile might get checked and followed. This is one of the reasons why your profile text matters a lot. Your description text should be up to date, and there should be a link. In our case it’s a link to a YouTube video. You should also have a pinned tweet, that features your latest stuff.