Invest in SEO and partnerships, later it will work for you
Validate if the problem you are facing right now is experienced by more users. If yes, jump-start building it as a side project preferably in front of a community ( Twitter in our case ).
This would for sure correct the course of your product very early in the development phase. While doing this try to find your first paid customer and validate this idea.
Once you find more ways to scale this to cover your basic expenses, become full-time to work on this idea.
Get started, but don't overcommit. Get started with a plausible idea, and do everything you can to test its validity early on, then bail if it's not working.
It is a marathon, not a sprint. Patience pays off.
Just start! That's the most important thing. Once you start work on your idea, validate it first and then constantly talk to your users. There is no one who knows better what your app/product/service should look like than your customer. Try to improve your service every day. And service/product is not improved, only, when you add new features. It is also enhanced if you work on your marketing, customer service, support, etc. As long as your customer is in the center of your next move (improvement), you're safe and sound.
Create a template to document your ideas.
Create a process to build and validate your ideas.
Always be building. Validate often. If validation starts to weaken, move on to the next idea.
You'll likely have hundreds of partially built products before you find 1 that is successful. It's part of the process. Keep building.
When you have an idea, make sure you're just as excited about the distribution method as you are about the product itself.
Building a product is EASY, finding customers is HARD. Make sure the best part of your idea is how you'll get people to find it!
1. Do something nobody else is doing. don't try to do something that has an obvious direct competitor. it can be a remix of other things though—ultimately all creative works are remixes or mashups.
2. Charge all your users, always and from the beginning. have a free trial perhaps but don't waste your time dealing with people who don't value your product/service enough to pay for it. if nobody will pay, make something else until someone will. this is your compass.
3. Stick to it: keep doing stuff every day. Complice itself can be really helpful for that! It's all about taking daily actions towards big complex meaningful projects. You need to not just do stuff, but keep orienting towards whether what you're doing is moving you towards what matters. I would have failed at building my business several times over if I hadn't been using it myself the whole time!