Once you have a portfolio of skills you can use professionally, how can you "make a quick buck"? Most alternative revenue streams described by developers are either grown slowly (eg. side-business) or require already established and trusted profile (eg. Upwork) and plenty of time to actually complete the project.
Optimization for yourself / "quick bucks" doesn't work for the client. There is no reliable fast path to greater wealth, it will always take putting in more, and higher quality effort than your peers / competitors.<p>This is why getting to the (partial) freedom to choose when & what to work on takes time. You have to earn (in terms of trust) your way there.<p>It's more than technical skills too. You will do better with non-tech skills in sales, relation, and expectation management.