How long do you think a startup needs to spend time on their Campaign before launching in PH?

If you are familiar with Product Hunt, and have things like a video and screenshots ready to go, I think a week is plenty of time. If it's your first time I would leave a few weeks to spend some time on PH posting and getting to know the community, and finding a guide to launching and such.

Most of the guides I've read state 4 weeks is the minimum...

I started a few months ago when I was thinking about it, a few mins a week to a few hours it all depended on what I started, a new screen design can quickly takes time when a text can take you just 1 min and come back to it 100 times on it week after week. I started also to look around what's happening on PH and start to become a member of the community, then I started to made my designs there and there, then I changed my mind, restart again, got a new idea, etc... After that I started to made my texts “ Tag line “, “ Intro “ , “ First Comment “, I wrote once, then twice, etc... I asked the people to tell me what they think about it, too long, too short, then corrections, etc... I tested the result on different app who make your project look like on PH page, then tested on PH and saw that the app wasn't up-to-date with PH numbers of characters, then rewrote again ( thanks to them... ). Finally, all was done 3 months ago, so that give me the time to made all the others customs pics for all others social networks with the same design of PH to launch on all of them. And now, im waiting to to finish my app and hope to launching soon 🤞🏽.

Probably more than a month! @galia1999

It depends, I think a 2-3 months would be a good amount of time if you're brand new to PH and it's your first time launching. You definitely need to invest some time getting to know the platform and learn how other products succeed and what they did to get there