How do I get subscribers for my upcoming page in PH?

So, today I finally decided to create an upcoming page for my product- a PowerPoint plug in that let's you create on-brand presentations at half the cost. Here's the page: https://www.producthunt.com/upcoming/instaslide How do I get people to subscribe for my product? I'm planning to give all the subscribers a free 10$ basic plan. Any ideas?