Viết. Đọc sách. Mua một cuốn từ điển vần và đây sẽ chính là “người bạn” đắc lực nhất của bạn. Học từ mới một cách chủ động.

Given the above summary, write a detailed text in English for it.
The more you write raps and rhymes, the more raps and rhymes you ultimately know. As you write rhymes, practice coming up with multiple variations on the same rhyming words. These clusters of rhymes will serve you well when you begin free-styling, because you'll be able to think of something quickly if you've used these rhymes before.  Try different exercises, like picking five words at random and working them into a rhyming structure of a few lines. Don't worry if what you're writing isn't "rap." Just keep the pen moving. Building good habits of journaling and writing will keep your mind disciplined toward words and thinking in terms of composition, something you'll have to do very quickly if you want to freestyle. If you hope to be able to freestyle, words are going to be your medium. As a painter uses paints and a sculptor uses clay, a rapper uses words, so you need to gather as big a pile of familiar words you possibly can so that you can draw on them in your rhymes. Reading a diverse variety of books, comics, online articles, and magazines is the best way to do this. Read biographies of rappers. You can kill two birds with one stone by reading about hip-hop while simultaneously improving your vocab. This will soon be your best friend in the world. Look at a rhyming dictionary less as a crutch and more as creative resource. It's not cheating to look up rhyming words while you're in the middle of writing some rhymes, because it might jog something loose you'd never have thought of previously. A good, cheap dictionary and a thesaurus are great resources too. Your rhymes will eventually be a lot more interesting the greater the variety of words becomes. SAT or GRE study guides are great vocabulary sources. Look up words in rap songs you don't recognize and study the definitions. Hip-hop is often jargon-heavy, using regional words, locations, and phrases, so it helps to look things up online. Chief Keef's "Love Sosa" doesn't make much sense if you think it's about the baseball player. Try taping up notecards...