When I was launching Klu.so, I took 5 weeks of being extremely active on Product Hunt. For all the people I interacted with, I made sure to connect with them outside of Product Hunt, either on Twitter or LinkedIn.
All the people I had interacted with, I kind of knew they would find value in Klu.so. So, I was in contact with them much before Klu launched. For some of them, I even gave Klu to try beforehand to get their feedback. Also, if you are making sheets of these people, which I highly suggest, because these people will become your best friends later on in giving you feedback about the product - what they love and what they hate.
So, make sure you have the right strategy in mind. Make sure you have set up your analytics, on both the app and web, so you can follow important events too.
Tell me what your plan is and I will help you make it even better.
And have fun!