This is a very easy question to answer, not all of you will agree with it, as it can vary. But if you have a growth mindset you will at least consider my opinion. One thing I want to clear is that this is my opinion.
Let us get started.
You should invest your first (maybe second, third, or a portion from all your incomes) in yourself.
What does it mean?
It means that if you are a developer buy some great courses, if you are into physical objects, buy good tools, buy books or whatever that will increase your knowledge and add value to you. Just empower yourself and more money will come to you just because you deserve it. Remember, knowledge gives you the power and as I increased my knowledge I started charging more and more to my clients. Thus resulting in even more money. I started from $5 just like you are starting now. No difference. This is my personal experience and I think it will add value to you.
See you soon