It *may* be possible to have an idea by the size of the spurs (Located next to the vent) with larger ones on males. This is not 100% accurate, but it is true of my one female and one male, with the male having huge spurs and my girl having little ones. Like I said though, this is not 100% accurate.
It's also almost impossible for a beginner with just one snake, so no basis for comparison.