In the quote on the title page at the beginning of the novel, who is the "gold-hatted" lover?

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Thomas Parke D'Invilliers is both a pen name of Francis Scott Fitzgerald and a character in his first novel, This Side Of Paradise. The epigraph for Fitzgerald's The Great Gatsby features a poem ostensibly by D'Invilliers called Then Wear the Gold Hat.

Then wear the gold hat, if that will move her;

If you can bounce high, bounce for her too,

Till she cry "Lover, gold-hatted, high-bouncing lover,

I must have you!"

These words seem to indicate somebody using material deception in order to win a girl. In other words, "bling" yourself out (for lack of a better word) so that a woman who would otherwise not notice you will pay attention. This is precisely what Gatsby does -- he wears a "gold hat" (not literally, but figuratively) to win Daisy.