You figure out how to get a job that supports you. A digital nomad is not some job title. Saying I want to be a digital nomad is like a seven-year-old saying I want to be famous when I grow up and assuming you get paid and fed for being famous. Here are a few things you need to know from a former and successful digital nomad:

Most people who claim to be digital nomads aren’t
It would be best to have a job you could do from any remote location on the planet first, or you were a doomed failure.
Most actual digital nomads started with a considerable cash reserve.
Less than 1 in 10 actual digital nomads can keep it up for more than 18 months.
No matter how good your IT skills are, someone from India or China is better and will probably bid $5 or $10 for a job you will need to pay $100+. This is why most digital nomads are not in IT.
Most of the actual digital nomads live a far from glamorous life. Having one hotel room for 8 to 12 people is common, and I hope you don’t get thrown out because of it.
Your embassy will probably not help you when you go broke or get stuck; this is especially true for Americans.
The chances of you having more fame or money than when you started is next to nothing.
Don’t assume you can get a job on the side if you run out of money; in most places, you can’t do this legally. I have seen digital nomads have to turn to basically illegal slave labor or turn tricks at half the rate of local prostitutes to feed themselves.
It is pretty easy to run afoul of immigration rules as a digital nomad, and you do not want to end up in an immigration detention center anywhere in the world.
The deportation proceedings, if you do run afoul of immigration rules and get caught, could have you in a detention center for more than a year in conditions that would make you happy to be a kid in a cage.