Learn Python/web.py. Powerful framework with no learning curve. More importantly, proportionate to how easy it is to learn, it gets the job done, fast.

Anything that saves you time is good, because there will be a lot of repetition. If you're doing web development, use single quotes instead of double quotes (to save shift keystrokes). Use Jade/Coffeescript/SASS instead of HTML/JS/CSS. Learn jQuery. Use Bootstrap instead of doing your own design, unless you also want to sell yourself as a designer, but tell clients you'll also provide design (they can't tell the difference). Build up a library of code that you can reuse (basically anything you find yourself copy/pasting or rewriting between projects). Use quick-and-dirty solutions instead of long, conventional ones as long as (a) it results in a net decrease in time spent, (b) the product quality stays the same, and (c) the client doesn't know or doesn't care.

Build MVPs for clients from start-to-finish by yourself instead of working with others unless the overhead is compensated by money. Learn how to write, because being fluent in English will get you surprisingly far in a market where a lot of your competitors can't use punctuation.

Charge per-project, not per-hour. This way you're rewarded, not penalized, for being a fast worker.

Experience: freelance programmer here who dropped out of college and never had a job; making enough to survive and spend the rest of my time on other things.

Find a business owner that needs web development done that doesn't have time to do it herself or knows a little bit less about it than you.

You can charge that business owner now. Any language will work and there are trade offs for each language.