Proofreading is a slightly unusual skill and it is true that some people naturally possess the required knowledge, somewhat like some people are able to act without going to drama school while others need years of training before learning how to be an actor.
The same can be said about proofreading, although of course you would have to have been very good at English in your school years to have obtained the necessary English-language skills to enable you to successfully complete the job.
Generally speaking it is fair to say that people who are extremely keen readers and-or writers tend to make good proof readers possibly without ever having to take any real proofreading training.
Many proofreading traits are inherent in that it is not just is perfect grammar with every comma and full stop in the right place, it is also having an eye for words or phrases that simply sound better than the text you have been given, and the ability to make a piece ‘flow’ simply meaning making it easier and more interesting to read.
Having said all that, it is also true that many people who have a keen interest in writing and perhaps have spent many years writing stories or blog articles simply do not possess the natural ability to proof articles.
There is also another set of people who again can write well, and proof well, but are unable to proof read their own articles simply because they are blinded by their own words, meaning that their brain does not recognise mistakes in the text and automatically fills in any blanks and overlooks any errors because when reading the text back their brains automatically correct it in their own minds, so it reads well.
Ultimately a potential proofreader may not be able to perform the task without taking some kind of training before becoming a professional and taking on paid freelance proofreading.
Even those with very strong natural abilities in this field will always need a considerable amount of practice and perseverance in order to be able to competently take on what is often a very important or even crucial job for a client.
It is also true that freelance proofreading can become a very tedious process which requires some large degree of dedication. But this can very much depend on the type of work you are being given, because if a piece is badly written and lacks any real ‘flow’ it can be a painful experience trying to make the words interesting and vibrant.
The other side of the coin is that it can also be easiest job in the world, if the text is already grammatically correct, is about an interesting subject and is well written then professional proofreading can be not only is easy but also extremely enjoyable and interesting. So if you feel you have the skills and a good amount of interest in writing you really should consider taking on proofreading training as a possible career path.