You can only ever be as good as that which you read. Read only blog post and you will sound like a blogger. Read only classics and you will sound like a scholar. If you read enough you will become your own best critic. Stop trying to write better and spend that time reading the best material you can find.

The same is true for all aspects of language. If you want to speak better, don't watch TV news or LA sitcoms. Watch classic British comedy (Blackadder) or BBC science docs (Brian Cox) that will expand your practical vocabulary and sense of proper diction.