I am a Developer and I am building projects for 8 years already - they kinda all failed but every failure made me learn very important things. Currently I am again onto a new project and I got ~130 users now after 9 days - basically my biggest success I ever made so far.

What worked for me is the following:

1. Don't build everything before it is not really validated, you're wasting time. Maybe your idea sounds good in your head, but is it really solving any issues? You need to find out if there is actually really a demand for it.

2. I've launched my Idea as a closed beta first and I searched for high intend users, this means I searched online where my target audience actually complains about the problem I think my app solves. So a closed beta was my first approach to test if anyone would even have interest to join and I could test my apps core loop if it works.

3. The closed beta validated that the Idea could work but still the product is not validated, you have no Idea from a few closed beta users if they'd be ready to actually pay for it - so you either ask the few closed beta users in a google form poll or something equal if they would pay for any specific features and in general you ask for feedback there. I did it a bit different though, but it brought me to step 4

4. If you got that far, you should open your beta to get more users. For me a lot of my target audience is actually on reddit. I found many extremely relevant subreddits. It was still very difficult there, replies to pain signals converted extremely bad. I found some subreddits that allowed me to post about my project and just explain the idea - it wasn't really written like a pitch, I just asked people if they would use something I've built and I basically just explained the Idea - some posts alone brought me like 40+ users in 2 days - it is not much for some people who are extremely successful, but for me this was insanely much. I never managed this before with any project from the past.

5. You have to be dead honest with yourself and sometimes just shut down your own projects early, try not to be sad about it, you have to learn about every project you've tried what you did wrong and what you could do better next time. I am still unsure about my project as well, if it really pops off.

I wish you good luck though!

If you're curious, this is my current project https://valuepair.app