It's best to separate the broody and her eggs from the rest of the flock. Set up a nest in the dog crate. Put it where the rest of the flock can't access the nest or bother her. Make sure there are no drafts.
She'll need food (it can be her layer feed), water, oyster shell, grit. She will lay eggs until she has completed her clutch. Then she will sit on the nest around the clock except when she gets out to eat, drink, possibly dust bathe, and poo. The broody poo is huge and smelly. If you have her indoors, you'll want to dispose of the broody poo immediately.
Leave her alone and in approximately 21 days, if the eggs are fertile and everything goes well, they will hatch. Mama hen will keep the chicks covered for the first couple of days. As long as she isn't hurting the chicks, leave them alone. As soon as the chicks start hatching, remove the layer feed, if you used it. We use FlockRaiser for our chicks, but you have decide what you are going to feed mama and the chicks. Take the oyster shell away also.
We keep our mama hen and her chicks together away from the flock for the first few weeks. If the weather is good, we set up a dog kennel where mama hen and chicks can get outdoors without the flock injuring them. But the flock can see them, and after a few weeks pass, we start to let mama and her chicks forage with the flock during supervised visits. During this time, mama hen and chicks are still in the broody area at night. Watch out for fighting during this time, as mama hen will attack any bird that goes near her chicks.
When mama hen is ready to leave the chicks, she will start pushing them away from food and treats. She will start squatting and start laying again also. Depending on the weather and the age of the chicks, they can go out to general population or continue supervised visits.
There are advantages and disadvantages to having mama hen raise the chicks. No heat lamp is needed, mama hen keeps them warm. She will show them food and warn them of danger. They are adorable walking the farmyard trying to keep up with mama. Depending on the hen, she may or may not attack her humans when they pick up the chicks. I have seen even docile hens become very ferocious when she thinks her chicks are in danger.
