Recruiting a group of people to learn and share the langauge learning tips may be a hard work. Another way to learn Chinese might be easier: you can subscribe a list of Wechat public accounts that publish an article per day, from which you can learn Chinese by reading and writing the articles. For listening, you can go onto http://www.slow-chinese.com/. They have many great podcasts for Chinese learners. For speaking, you may want to find a virtual native speaker, which I think would not be difficult if you study in China, or have friends or classmates that are from China. Hope this helps.

可以建一个微信群啊

You can creat it you own, and invite someone who wanna study chinses and native speaker to help you all. Also i am happy to help you to improve the chinese.

I am a native Chinese speaker in the U.S. for college now. And I am trying to improve my English. If you like, we could become exchange friend to learn languages together. I would like to help you with your Chinese. By the way, we can use wechat to talk with each other.