Writing, like all things worth doing, requires practice. I’ve learned through both school and college, but nothing has helped me improve more than by commenting and debating on internet forums. In nearly every popular forum on the internet, there are off-topic areas in which you can debate and discuss current events and philosophy. It is often a dog eat dog world where the slightest spelling mistake or grammical error can cost you some if not all of your credibility. This is harsh, dirty and real training for what people expect of you professionally. Pactice and you will succeed.