How do you announce your product to people without spending any money?

The income level of https://www.monitup.com is very low, I am researching what I can do without spending any money to keep my project alive.

My aim in short: Bring the project to MVP level and sell it with minimum cost, minimum time, minimum effort!

I need to advertise but my advertising budget is $0 :)

That's why I first started an AppSumo campaign:
https://appsumo.com/products/monitup-employee-monitoring/

Then I launched a Product Hunt:
https://www.producthunt.com/posts/monitup

Of course, a little bit of social media.

The result isn't great, but better than nothing...

Are there other platforms where you publish your projects like AS or PH? What do you recommend?