Dear Sir/Miss,
I have been doing proofreading, typing, editing and content writing for around five years. In these five years, I have worked for local magazines, newspapers and blogs. Most importantly, almost all my projects at my university were done with computers and we were given intense writing tasks. Going through all these learning ventures, I believe that I have improved my English skills good enough to complete your task with great success. Furthermore, because of my good pace writing, reading and editing, I can complete your task in a short span of time. I can also provide you with some of my writing samples. If you are considering me, please let me know the timing for your project.