Talking to a person in an English speaking country can be an incredibly fun and exciting adventure to start on. They'll be able to tell you about their culture, their customs, and give you a real path to the English speaking world. And getting mail is always a pick-me-up! Students of the World and PenPal World are both good online resources to finding a penpal. You can either use snail mail or email with your new writing friend. Though email goes much quicker, snail mail can be a lot more personal and exciting. Though you won't be able to correct your own mistakes, you will be able to keep up your vocabulary and discover the words you don't know (and then look them up!). If you don't use words, you're likely to lose them -- keeping a journal daily keeps the words and phrases fresh in your head. This journal can take on a number of forms. It can either be an English journal devoted to other's musings -- where you write down song lyrics, poems, and quotes in English that you like -- or it can be writing of your own: thoughts, venting, gratitude, or just devoted to one specific topic. This tactic is good for writing and recall. Take everything in your home and label it in its English name. The goal is to start thinking in English; at home, you'll be more likely to think, "What's on TV?" if "TV" is right in front of you. Don't stop at what's in front of you (bed, chair, TV, lamp, refrigerator) -- go inside your cupboards and fridge. If there's a place you keep the dishes, label it. If there's a place you always keep the milk, label it. It'll help keep you organized, too!

TL;DR in Chinese:
找到一个笔友。 写日记。 开始做标签。