I believe the males will have either a white dot on their head, or will be entirely white. The females will have no dot? Gosh, I just don't know on the GSL. But, with all other sex links, the males are the ones with the white dots on the top of the head.
MS9325 is right. Males are white, pullets will be more redish in color. There is an obvious difference in them and anyone can tell the cockrels from the pullets if you have one of each sex next to each other. I'll post a link to Cackle's golden comet's page. You can see how the male vs. female chicks look there.