I have ten hens who are about 9 months old.   Since they came out of the brooder, I've been doing the same thing.  Every time I want them to go back into the run I bring out a yummy treat and yell "Ladies!"  and walk into the run.  (We live on an acre, and about 2/3 of it is fenced-in.)
 
Now I walk out the back door and they all come running and follow me into the run for their treat.  They're smart, these chickens!
 
I typically do this a couple of times a day since I don't trust my dog to be in the yard the same time as the chickens.