Coding for the web is crazy, because there are so many different services, snippets and styles all thrown together and interpretted by so many different browsers, operating systems and devices.
The only way to become an expert is to code. A lot. Enough to come across some version of every single different corner case and compatability issue. Every time you encounter a problem and eventually solve it, it's that much easier next time. I'd say it's the only way to make it easier the next time.
As we leave the era of IE6 and even 7 (because Microsoft is finally "forcing" IE updates), we enter into a new and equally challenging era of more moving parts and higher expectations. The only real way to keep up is to code. A lot.