Cut your costs to begin with to increase your chances of success, save what you can and start with a concrete goal in mind, say $50 per month increase for the next 6 months, then when you've achieved that goal (hopefully in 6 months!) think about what you've found and if there are ways to scale it.

Projects 'on the side' is renting yourself out hour by hour, it does not scale very well but if a side project is sold as licensed software (niche software more or less by definition) you could make out very well and if someone wants to license your source code instead of the final product you could make a big chunk in one go.

It's quite difficult to say what you can achieve without having a good grip on your situation and your skills but if I had to start over again from a day job I would do something like that.