There aren't many skills needed to become a typist. Good keyboard skills, good understanding of what people say and ability to transform data from audiotapes, paperclips, etc to are the biggest requirements. If you are required to handle administrative tasks like managing spreadsheets and databases, you will need experience and qualifications in those areas too.

Good communication skills, good command over English language (100% accuracy in grammar), time management skills and ability to work with the whole team are essential skills. Since typists handle almost all kinds of sensitive data, it is important that you exercise discretionary powers to determine who can see the data you handle.