Experience, portfolio, degree.
In that order I would say. If you can prove you know your stuff, and I mean really know your stuff, employers will more likely be willing to take you on. I would also try to enter in as an intern role as a start. If you do not have a degree, offering to work as an intern will be a great way to build up some experience. Depending on the company you might have to end up working for free, but at the end of the day, we have an intern working in our company with a degree and he is working for free and in fact when I was job hunting I noticed many companies are exploiting the dire situation with a 3 month unpaid internship to see your worth.
Once you have some experience and a portfolio to point to, start considering a degree, at the end of the day it may just be a piece of paper, and I know first hand that my "web managers" despite having a degree don't know their Google Analytics code from their button .png, but companies want degrees. Simple as that.
Once you have all three to hand, then you can really start to look further afield. Unfortunately HTML/CSS probably wont be enough. In fact how up to date is your knowledge?
Finally, some understanding of what is going on in the wider web development world away from the actual code, understanding how sprint cycles work, and some knowledge of development styles will be beneficial.