as Awgust lives in the U.S. I just presumed that I have to use the English spelling Avgust when talking about a Russian form of the name.
By the way - the correct German transkription of your name would be Iwaila. A "y" is used to transcribe this letter which comes right after the t in the Russian word for "you" (sorry, but I don't have Cyrillic letters...). So Russian "you" would be written "ty" in Germany.