One of the most important things is communication.
Speak English whenever you can. If there’s nobody around you, speak to yourself.
Do not be worried about grammar or vocabulary when you’re having a conversation with a native speaker. They really don’t care about any mistakes you make. For the most part they’re happy to talk to you and may be surprised how well you can speak their language.
Practice by reading all types of books, magazines and newspapers. The more you read the more vocabulary knowledge you will gain.
Watch every single movie, TV show and documentary in English. Even if it’s something like How I Met Your Mother. Shows like this improve your skills so much, you will get better from time to time at small talk.
It is best to not just stick to one thing but combine all of these tips and you will see that you can reach a level where you speak confidently and fluently.
Good luck.
-Goodluck Oby