The good suggestion is - speak. You have something that a lot of people want, which is Chinese. Arrange conversations with native speakres and practice. You don't need a many, just one or two people you're comfortable with.
But also speak to yourself. Train your mouth musscles and learn how to pronounce words correctly.
Also you need to expand your vocabulary if you want to talk about different topic.
Reading out loud has helped me a lot too.
And be patient. Doing all of these above will pay off, I can guarantee you.
Best of luck ;)