It's hard cus some breeds have different feathering, i'd try looking at a hatcherie's babies or other people's babies of the same breed and compare pics. I bought my chicks from a feed store and the chicks themselves r really informing. My (female) black australorps have really fast feathering, golden sex-link and barred rock is medium feathering, and buff orpington is slow feathering. Female chicks always have faster feathering than males regardless. Idk if this is helpful, but I'll see if I can find anything