Now that I got that out of my system -- it is apparently very difficult to
do if they are not showing definite combs yet. The roosters' combs
generally show before the hens'. You can also observe which are more
aggressive (usually the roosters). Some breeds have distinctly different
colors and other features, like the ones which are crested. We usually wait
for the crowing to start.
If you're talking about day-olds, find an oriental person to do it --
that's who the big hatcheries hire, because they seem to be much better at
it than others.
>How does one sex chicks?
>
>Don Bowen Awl Knotted Up Woodworking