If you don't mind, a word about the phrase: "Вы вольны исправлять мои ошибки." My understanding is that is a translation of "Feel free to correct my mistakes". If that's the case, then that "close translation" has some different tone attached. The English version implies a polite and respectful request, something like: "If you start correcting my mistakes that surely will only meet my positive response." However, the Russian version means something like: "Of course you might start doing whatever you want and correct my mistakes, and unfortunately I can't do anything about it".

So, what you really want to say in Russian is something like: "Свободно исправляйте мои ошибки" (=feel free) or even better "Спокойно исправляйте мои ошибки" (=feel relaxed).

Hope it helps.