People often ask me for advice on how to learn English. Everyone is different. I'll share some of my experience. I once learned English in Beijing University, but I mostly learned English on my own.
One thing I can tell is that, once you've started learning, you should try to think in English as much as you can. When you're riding your bike or walking down the street, just think about "how would I say them in English?" At first, it will be with simple words or word groups, but later you should think about bigger phrases and word groups. Now I'm in America, and for most time, I just think in English and speak it directly. It's amazing how much this helps.
For several years after I started learning, I was often afraid of trying to speak English with others because I didn't want to make mistakes. Finally I got over it. And while traveling in America, I tried to hang out with friends who speak no Chinese, so I have no choice but to speak English. I wasn't afraid to make mistakes and I don't mind others laughing at me. My English started improving more quickly after that.
It may be a good idea to ask any of your American friends to look at the way you're writing, and give you some advice.
