Since you will be around a lot there are many indicators that will help you identify egg layers:
1) egg size
2) egg color
3) hen in nest box for short time getting ready to lay, sometimes people think the hen is "broody" but shes just getting ready to lay. I dont disturb my hens when they are about to lay, it could cause them to find another place to lay, so you also know who's in the box by process of elimination. If not with flock they arecin the box (at least in my case).
4) later on, when hens get older (or if sick), start to molt etc., they will lose some of the color in comb and legs (unless already white or a very dark color) and wont lay. When color intensifies again they will start to lay again.
Thank you this is very helpful.