2. Realize that your mistakes don't matter.
When I was a teenager, I used to think that everyone at school was looking at me and judging what I looked like, what I wore, and how I acted. As I got older, I realized that no one really cared what I did; they were too busy worrying about themselves.
That's true of your English skill, too. The people you're speaking with probably don't care whether your grammar is good or bad. They have their own problems to worry about.
Not only that, but English speakers are already used to understanding foreign accents. Most English-speaking countries have a lot of residents who were born in different countries. So native English speakers have a lot of experience with speaking to people with different accents. They may not even think about the fact that your English isn't perfect.