HOW DO I SPEAK ENGLISH WELL?

The best way to improve your English, and to speak English really really well, is to just not worry about it!

Fluency first. Accuracy later.

Speaking English is not an "Academic" pursuit, it's a physical thing. So the best way to learn spoken English is to do it physically - put another way, to speak English well, you have to speak English!

This means that at first you must make a lot of mistakes. But that's OK. Concentrate on speaking fluently first, and you will speak accurately later more easily.

When you are learning English, you will make mistakes. Native speakers expect you to make mistakes. It's OK. Just don't worry about it.