Get some training
There is no set path to becoming an editor. Most editors have at least one university degree. A few have a qualification in language, linguistics, writing or editing. Many of the best editors are accredited under the national accreditation scheme.
The Canberra Society of Editors runs day and half-day courses on topics such as proofreading, copyediting, web editing, on-screen editing, and so on. Courses are run in response to demand from members, so the actual content varies from one year to the next.
Formal training, leading to a recognised qualification, is available from one of the institutions listed on the IPEd website
You should approach these institutions directly for more details. We will not recommend any one course or another: it is up to you to choose a course that suits your own circumstances. You are always welcome to attend our monthly general meetings (free to attend) and you can ask practicing editors for their experience with these providers.