So we all know how fun it is to get that mixed-breed surprise at the hatchery, or how some places just don't know the breed of the chicks your buying, or you just want to know the gender! Well here are some steps how to tell the gender and breed of your chicks. But remember! Some breeds (Such as Old English Game Bantams), are REALLY easy to tell the gender, and others can take MONTHS! (Such as Easter Eggers) Some even like us to think their roosters, only to lay an egg.

~ Some Stuff you Need to Know ~
So heres some stuff you need to know. First off, please don't be asking the gender or breed of your 3 day old chick. SOME breeds you can figure out if we know what hatchery (if you ordered from one) you ordered from, and if the chick (or Duck, or turkey, but I won't be putting steps for telling their gender or breed, but a lot of this info can be applied to those as well) is unique. As for the gender telling, you must know this.
Saddle feathers
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(Above is a rooster whose feathers are labeled. Click for larger image)
They are right by the tail, and often cover the end of the wing.
A rooster has pointed, often long, saddle feathers. Their tail feathers tend to be longer, more rounded, and shinier then hens, but not always. I've only ever heard of EE's (Ameracauna or Aracauna mixed breed) having pointed saddle feathers when being hens, and even so, when they got older they lost the pointed feathers.

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As you can see, on roosters, the saddle feathers are very apparent, vs hens, where it doesn't make much of a difference.
Wyandotte rooster, same color as the hen above, so you can see how the saddle feathers are apparent, even on the same breed
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Another thing is, hens do not always have a smaller comb then the rooster. In most cases, yes, but hens can have larger combs (depending on the breed of course), and hens can have large combs in general.
~ Telling the Sex ~
So here are some steps to telling the sex of most chickens, however, some chickens are later, or earlier bloomers. This is a general guide, and it varies.
~ Comb
Lets use OEB's as an example here. I currently own about 20 OEGB chicks. They are about 2 weeks old, and I can already tell the roosters. Yes, some may become obvious roosters, but I can already see 5 roosters.

(My picture)
Turkens can be hard to sex, due to having large combs, but I know this was boy. As you can see, he has a large, red comb. That is a classic sign of a rooster. The earlier the comb is red, and the larger, the more likely the chicken will be a male. However, after about 6 weeks, all chickens should have some reddening in the comb by then

This 7 week old cochin hen, as you can sorta see, has some pink in her comb. This is normal for hens, but if its extremely red it suggests rooster.

~ Feathers ~
Another way to tell the sex, is by the feathers. While by this time the gender should be obvious, if your still new, or bought it as an adult, here is a hen and rooster labeled the differences, and what makes it a hen, and what makes it a rooster.
ADD PHOTO HERE LATER OF ROOSTER
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ADD PHOTO HERE LATER OF HEN

~ Spurs ~
Now, spurs are not really a way to tell the sex of a chicken. But its still fun to learn about them :)
Now roosters tend to have longer spurs, and (at least I've noticed) start growing around 6 months. This varies breed per breed. Some hens grow spurs, some don't.

Though it isn't very noticeable, this rooster had about 2 inch long spurs. We never knew his age, however his spurs did grow the longer we owned him.
ADD PHOTO OF HEN WITH SPURS HERE
Hens can get spurs, though they are less common and often shorter.

~ Crowing & Egg Laying ~
Crowing and egg laying is what 'The lazy man's way'. Essentially what you do is wait to get eggs or hear crowing. You don't have to do anything, other then to see who crows and who is laying. That said, in rare cases, when you have only hens, sometimes a hen will start crowing, and began to change sexes. This is rare, but some people have experienced it. Some cases, the hen will simply start crowing, but keep laying eggs.

~ Breed Telling ~
For breed telling, give as much info as you can when asking others.This includes age, gender, suspected breed, if it came from a hatchery, which, if you do or don't know if its a mixed breed, etc.