Regarding the product idea, it varies from an itch I have, to a neat idea but I’m not the target audience, so I ask around (esp. on Reddit), to someone asking me to make them something and I ask if instead of billing my hourly rate, I can sell them a productized service. I jot down my “itch I have” ideas regularly in a to-do app.
I’ve tried building the product without designing it first (jumping straight to code) and I’ve found that it has always been a mess (re-designing multiple times in code).
I now design the concept first (in Sketch) and only once it feels right, I get implementing. I create a basic styleguide and reusable symbols, which I reuse throughout the app/product.
Then I get implementing. Once I have something that starts to work, I tease it out on Twitter/Reddit and see if people like it. If it gains steam, it gives me enough wind under my wings to continue developing it.
I give myself X amount of time to ship (otherwise the project takes forever).
Once “done”, I send it to a few friends using TestFlight/MS AppCenter for beta testing.
If all goes well I prepare a launch page and launch on ProductHunt.
Depending on the niche I communicate with bloggers on launch day (a big chunk of my buyers are referred from these blogs even years later).
Regarding time and idea picking:
I just do what I’m psyched about, whenever I want. I’m lucky to have financial security at the moment.
What I wish I had in a partner:
Someone who can complement my skills: someone better at design who can still develop.
I’ve already talked with dev acquaintances about teaming up for weekend projects. Would definitely be fun and I don’t care as much about getting 100% of the pie.
The to-do list:
I put almost everything in a to-do, but only check it towards the last 20% of the project. I tag everything as e.g. Design, Client, Server, Marketing. Once the MVP “feels” done, I go through the list to see what’s missing.