If I Were You - P. G. Wodehouse 1931 - Herbert Jenkins Limited, London - First English Edition, in early issue dust jacket (1940) 'Kind hearts are more than coronets'

When Antony, fifth Earl of Droitwich, is spotted in the rose garden kissing Violet - rich, beautiful and as hard-boiled as a fashion plate - his future marriage and the security of his stately home seem certain. But when his disreputable old Nanny, Ma Price, spills some distinctly unsavoury beans Tony's life is turned upside down.

His new position is not so uncomfortable as his shocked family fears: he has fallen head over heels for transatlantic charms of Polly Brown. She is a manicurist and no fit mate for a belted Earl - or is she? And is he? It will take all the efforts of Tony's brother Freddie the Infallible, with the help of Price's Derma Vitalis hair restorer, to comb out the tangles and find a remedy to salve everyone's pride - and their pockets.
  With the dust jacket illustrated by W. Heath Robinson.

If I Were You was based on a play of the same name by Wodehouse and Guy Bolton which, according to Taves, was published but never performed. It was serialised in American Magazine (US) between April and July 1931 and in the Daily Mail (UK) from 5 June to 3 July 1931.

The book was re-adapted for the stage by Wodehouse and Bolton under the title
Who's Who? It received its first performance at the Duke of York's Theatre, London, on 20 September 1934, with Peter Haddon as Tony and Ivor Barnard as Syd Price: Haddon had previously played Cuthbert in the 1924 film of The Clicking of Cuthbert and played Bill in the 1939 film adaptation of Good Morning, Bill.

Bolton later adapted the play as a musical,
Who's Who, Baby?, with music and lyrics by Johnny Brandon. It opened at The Players Theater, New York, on 29 January 1968 1, though, according to McIlvaine, Bolton asked for his and Wodehouse's names to be removed from the programme.

First published in US: September 3 1931 by Doubleday Doran, Garden City, New York
First published in UK: September 25 1931 by Herbert Jenkins, London

References: The Russian Wodehouse Society. Madame Ulalie. McIlvaine A44b.
pp. 280 [8 ads].
First edition in orange cloth with black lettering, borders and publisher’s logo.
In later issue dust jacket, listing
Quick Service (published October 1940) printed as latest title to the rear panel.
  Condition: Near fine, 2mm closed tear to tail of spine, light foxing to foredge and preliminary pages, in very good minus jacket, 3cm chip to tail of spine, rubbing, wear to head of spine and corners, evidence of tape repair to verso, small 1cm price sticker to top corner of front panel.   Ref: 106739   Price: HK$ 2,200