[nfriedly]

Running "lint" tools on your code can be helpful for catching basic things, http://eslint.org/ is my favorite one for JS, I know ones exist for other languages.

After that, ask for code reviews. If you don't understand why the reviewer is suggesting a change, keep digging until you do.

Also, as partisan said, reading through the code from the other devs will be a huge win. Even if it doesn't follow "best practices", it will show you what's acceptable in your company which is arguably more important right now. And, again, if you come across something you don't understand, ask about it.

Oh, and you need loads of testing to help avoid regressions. Some manual testing is good, but you really want automated tests covering most things.

[pzk1]

Thanks. Excellent point on the "reading other dev's code even though it's not best practice". Yup you are definitely right, most of the regressions are because of manual testing. But the team are very comfortable making changes and doing things "on-the-fly" + manual testing here and there, but they get away with it by being talented coders in the first place, which is the point of this post anyway. We are doing PR regularly though.