The larger and darker the comb + wattles the more likely to be male, the best way is the shape of the feathers around the neck. Girls are rounded at the ends, boys are more pointed
We have orps and they are lovely - hatched last year unfortunatley 2 of the 5 were male so had to be re-homed. Hens are lovely though and very comical and motherley.
My only warning is that they are prone to becoming broody and it lasts weeks.
Good luck