They will start to come in anytime now. Around 4 months you start see rooster wattles and a few weeks later for the girls.
Pullets do have wattles, but they tend to be smaller and take a lot longer to grow in and turn bright red than a male of the same breed.
Generally, once the combs and wattles start turning bright red on a pullet, that's a sign that she is getting very near to laying age.
It's usually around 5 to 5.5 months when the girls give you that first egg