Sharpening your language skills isn’t what you just do one-time and forget about it. It has to be something consistent and really practical. That is why I itemized a few things that I found helpful in delivering a very good diction in English.
Some of the things itemized here are not conventional ways of learning a new language but they have been proven to help in sharpening ones language skill, both in written and the spoken form.
Do the following to speak and write better English:
Engaging in real-time communication with a native (or very good) speaker:
When you engage in a conversation consistently with someone that speaks a language fluently, you get to learn the ways the language is suppose to be spoken. This is something that is not negotiable. You can’t learn how to speak a foreign language in a book.
Making a dictionary handy to look up new words
When you just heard a new word for the first time, it’s a good time to make it stick and learn several other ways to use the word correctly. The dictionary comes useful in doing this. Having a dictionary is as important as having it handy because it is important to look up those words before hearing those new words the second time.
Writing down one’s thoughts regularly
Writing in a language is an infallible way of even learning to speak that language. The reason is that, when one is writing (or typing) in a language; one usually also speak the words that is being written. In that way, writing helps one in speaking and vice-versa.
Listen and watch multimedia materials
The effect of this is close to the one you get when you engage a good speaker in a real-time communication. The advantage to this one is that you can continue to listen or watch a single piece over and over again. By the time you are done looping through a piece, most times, you are sure that you have mastered the array of words present in that piece.
Movies, music and educational materials are useful in this category. They help to tune ones brain to better listen and communicate in the new language.