The most obvious way to improve your coding is to write more code.
This is a bit too simple: writing more of the same, in the same style, usually won't cut it and unfortunately I've seen people being stuck like that for years: always producing more code, without any improvement whatsoever and instead just repeating the same mistakes. Once those mistakes become a habit they are extra hard to get rid of. So actually writing more code can be worse :]
What you really should be doing is write more and from time to time different code, combined with learning through either reading others' or continuously asking yourself 'how can I improve this' followed by e.g. a trip to StackOverflow to find out.
This is a bit too simple: writing more of the same, in the same style, usually won't cut it and unfortunately I've seen people being stuck like that for years: always producing more code, without any improvement whatsoever and instead just repeating the same mistakes. Once those mistakes become a habit they are extra hard to get rid of. So actually writing more code can be worse :]
What you really should be doing is write more and from time to time different code, combined with learning through either reading others' or continuously asking yourself 'how can I improve this' followed by e.g. a trip to StackOverflow to find out.