You can't (at least not in the computer/web dev field). You could work odd/not normal hours but you will still be putting in the same ~40 hours a week. That's all unless you have some kind of passive income/wealth from parents & relatives.
I haven't worked 'regular 9-5 hours' for any meaningful length of time (i.e. beyond a few days here or there), basically ever, and I entered the field 15 years ago.
I've worked for state & federal government departments, contract agencies, and I now work directly with clients through my company.