To speak English fluently, you need an extensive vocabulary. Grammar may be a secondary factor, but you certainly cannot ignore the foundation of every language: vocabulary. The reality is that you cannot memorize the entire English dictionary in just one day.

SPEND ABOUT 10 TO 20 MINUTES every day

Set a daily goal for yourself, but make sure it's realistic and stick to it. Start with a goal of one new word a day, then gradually build up to two to five new words a day. Ask yourself how much time can you devote to learning a foreign language each day? Can I achieve my goal with about 20 minutes a day? What is important in the process of forming a daily English learning habit?
Of course, don't forget that 15 minutes spent studying every day will definitely bring better results than spending only 30 minutes a week. 

HAVE A VOCABULARY NOTEBOOK

Equipping yourself with a vocabulary notebook is not simply taking a notebook to take notes, but rather you are storing all the knowledge you learn in a single source. If you like using apps on your phone, don't hesitate to use them. It is important that you establish and develop a system for yourself to store the vocabulary you have learned. From there, you will easily view and re-systematize them every two weeks.
NOT AFRAID OF MISTAKES

Sometimes it's hard to combine all the rules and vocabulary into a simple English sentence. However, don't let the fear of saying the wrong thing keep you from saying anything. Even if you think you said the wrong thing, keep talking. Most of the time, people will still understand what you're trying to say, even if you make a mistake. In addition, the more you speak, the easier it will be to learn English communication vocabulary faster and more accurately.
LEARN FROM PEOPLE AROUND YOU

Not only do you learn English from teachers and textbooks, but anyone who speaks English can help you practice the language. Imagine how you would feel if someone asked you in your native language: how to pronounce a certain vocabulary word? Would you be angry? Of course not! You will probably feel very happy to help them learn pronunciation, just like when you make mistakes when pronouncing and people will be happy to help you correct them.

If you know anyone who speaks English, whether it's friends or colleagues, take the opportunity to practice and learn from them.