As a solopreneur, how do you plan for a product?

I use Milanote, Notion, Figma. Sitting down on the weekend and writing a roadmap for itmeo.com

Ask people above you in linkedin for feedback

You're in the right direction by asking in a community forum like Product Hunt Validating an idea ~2 weeks - Don't build a product yet. First, build a fantastic landing page for your idea and focus on capturing emails. - Join community forums like Product Hunt, Indie Hacker and ask for opinions and feedback on your idea, and share your landing page. - Join niche groups on Facebook groups, Discord channels, Reddit and ask them about your idea, and share your landing page. - Then build a working MVP, update your email subscribers, charge for money. If you get paid enough to cover your maintenance costs for at least 3 months (this is an arbitrary number, but the more months the better), then keep on going. If you don't have the capital to start a new project, always always always charge customers upfront. Otherwise, you'll lose money, time, and energy by building something people don't need. Sometimes you can will your project to success by just being public and consistent, like posting your project progress publicly on X (Twitter) or whichever social media you prefer. We see many instances like this, so it's something worth trying. If you can code your MVP, then code. No-code tool is easy and all, but it won't be a unique experience. Hope it helps!

Ship quickly, tell everyone what you are doing, try to find audience in your friends, iterate fast and most important - DON'T GIVE UP. I really liked MAKER BOOK by @levelsio. I don't use any no-code tool, because prefer to build something myself than learn no-code tool :D