How can we tell which chicken is laying?

[PixChix]

We have 6 young chickens, they were hatched Mid March 2018. We just started getting eggs about 10 days ago. Started with one per day, now we are up to 3. Is there a way to tell which hen is laying and which are not without actually catching them in the act? They are all light to medium brown. Breeds are Delaware, Black AustraLorp, Orpington, Red Production. TIA

 

[50-45-1]

I would not be suprised if all 6 are begining to lay.
It takes time for a hen to lay regular, and all hens will take days off
A clue will be a bright red comb.

 

[PachecoPeeps]

Bright red combs and waddles, squatting, practicing in the egg boxes, moist vents. There’s a way to check between their pelvis area to see how wide it is. There’s an article on here about it.