Increasing the number of consumers by using promotions on social media

For this project, I am looking for someone to help increase the number of consumers by using promotions on social media. Specifically, I want to focus on doing promotions through contests on Instagram, and I would like to target existing customers. I am looking for someone who has the creativity, knowledge, and experience to develop engaging contests to help expand my customer base. Ideally, the freelancer will have extensive experience in developing and launching campaigns on social media and know which tactics and strategies work best when trying to increase consumer engagement. Above all, I want to partner with someone who can help create long-term success for my business.