If you have tried any other method and you failed then this can be your last resort. Follow the strategy below.
Follow as many people as you can and write as many tweets as you can daily, but ensure the tweets are not irritating to the followers you already have so that you do not risk being muted or unfollowed altogether. Your best bet is to reply to interesting discussions. Remember to follow those who share the same interests with you. Include every range from those with a small number of followers to those with a large following.”,
Participate in discussions and remember to be nice to others and to contribute meaningfully.
Do not just curate content i.e retweeting or sharing links but also create your own content by letting people know your own thoughts as well.
Pin a tweet which you feel can give people more info about the person behind the Twitter handle. Choose beautiful images for your profile and Twitter background. If you want to use your account for business purposes then the username must be short and professional.
Learn how to write captions or how to write social media posts in general.
Do not participate in the follow me and I will follow back kind of activity. Believe me, you do not want to attract people who do not share the same interests with you. Those people can later become a menace and cause you sleepless nights or worse still make you ditch your handle later and all your effort will be in vain.