Possible Clues:

• Elegant hairstyle, and what the circled letters give to 17-, 30-, and 47-Across?
• Pinned-on-top hairstyle
• Hairdo often held together with bobby pins
• Rolled-up 'do
• Classic hairstyle ... or a hint to the puns in 17-, 25-, 39- and 51-Across
• Rolled-up do