Don tells us he was born in 1949 in Kansas City making him around 30 at the time of the original adaptation. During the ‘montage’ Don expresses how he lied about his age to join a night club union to make money, be that as a stripper, in drag or as bar staff.
I have put Don in a Latin dance outfit with plum coloured shirt and pin stripe detail on the trousers as I like to think he has two alternate lives but also uses the torusers for work, and he goes with this outfit as the most suitable he owns for the audition.