Green’s Dictionary of Slang

(Aus.) usu. constr. with up, to dress up in a showy manner; thus pooned up adj., dressed up.

1943		Baker Popular Dict. Aus. Sl. (2nd edn) 61: Poon up, to dress up, especially in flashy fashion.
1945		Baker Aus. Lang. 206: Poon up, to dress up, especially with considerable care.
1951		D. Stivens Jimmy Brockett 48: Some of ’em were young lairs, all pooned up to kill.
1965		T. Wolfe Kandy-Kolored Tangerine-Flake Streamline Baby (1966) 17: All those sequinned giblets pooning around on flamingo legs.
1972		Chipper Aussie Swearers Guide 48: Pooned up, dressed to impress, often with sexual success in view.