Invest a lot of time in creating a magnetic twitter persona.
The good news is that you can just reverse engineer (ie., study and isolate elements that work) your competition or influential twitter users that cater to the same market as you.
Pay attention to what they tweet, when they tweet, how they respond to people, and yes, hashtags matter.
Pick a niche and tweet and retweet the hottest and the latest news in that niche. Reply to other tweets. Engage in discussions. Don't focus on followers. The amount of followers you have is pretty much irrelevant. It's your influence that matters. Focus your efforts on getting replies and retweets.
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