I often try to help people on BYC on re-homing their extra roosters. After mentioning Craigslist many times, I've decided that it's probably time to have a step by step instructions on how to post on Craigslist.
Step 1: Create an Account
If you don't already have one, you'll need to create an account. If you do have one, you can skip this step.
They'll have the option to log into your account, or to create an account. Below "Create an account" type out your email address and click "Create account." 
Craigslist will automatically send you an email to the email you typed out. Once you get the email, click on the link that they provided. That shall take you here (Picture below):
There, you can click "Go Passwordless," or create a password. After that, you will have your account.
Step 2: Create a Posting
Once you're on Craigslist's home page, click "create a posting" on the top left corner under "craigslist."
Click "for sale by owner" whether you are giving your extra roosters away, or selling them. 
Click "farm & garden - by owner." Even if you are giving your extra roosters away, do not click "free stuff." Craigslist doesn't want any animals on the free section.
Step 3: Creating the Post
First, type out your title. I typically title it "Free Roosters" or "Free Roosters to Good Home, Meal, or Tick Control." The best title would be "Free Roosters to Good Home." You don't want the title too long. Next, select the price. You'll need a number. It can be any number, but I suggest typing in 00 to clear up any confusion. If you put in any other number, some people will think that you are asking that number as a price, even though the roosters are free. Of course, if you are selling them, please put their price. Next, type out the name of your town and postal code. (Craigslist will require you to have a real town, and a real postal code.)
After you are done filling out the top part, fill out the description. State how many roosters you are re-homing. State their breed(s) if you know them. State their ages if you know them, and if possible, state their hatch date. If they have names, state those, and who is who. In the picture below, I kept things basic, but you can say a lot more if you want. You can even state their background story if you want to. If they are mean, you can state that. If they are a barnyard mix, and you know what they might be, feel free to say what you think that they are. I like to say "to good home, meal, or tick control." You don't need to say that. If pet, state that. If you don't want them to be a meal, state that. As far as for tick control, be warned and ok with the fact that some people will pick up free roosters for tick control, but might not be providing them a safe, secure coop. They may pick them up, and have them free-range around their yard, feeding themselves, until a predator gets them. If you are not ok with that, say to good home only. If you are re-homing multiple roosters, finding a home that won't eat them, or have them as tick-eaters only, might be a challenge.
In the picture above, you can see that I filled out the posting details. That's not required, but I like to fill it out for fun. 
Step 4: Location
After you click "continue," it will take you here (picture below). A location is required, though you don't need to fill out "street" or "cross street." A city (or town) and/or a postal code is required. Once you've filled out your postal code, click "find." It shall give you a small map of where you might be located. Once it has done this, click "continue" again. It will take you to the next page. Do not put your address anywhere in the ad (e.g. 00 Something St.).
Step 5: Pictures
Here (pictures below), you can add images, though it's not required. I strongly suggest pictures, because some people won't click on an ad that doesn't have pictures. Click "Add Images." Tip: The first picture will be the "featured" picture, so make it the best picture. You have a maximum limit of 24 pictures. I sometimes will provide all 24 pictures, but only 1 will be ok. Do not post any pictures that are screenshots, and make certain that the picture is yours. Try to post the most up-to-date pictures of them if possible.
Start adding pictures.
Try to post pictures of all the roosters that you are re-homing. If you can't, that's ok. If you want to add some more pictures later, you can. After you are done uploading all the pictures that you are planning on posting, click "done with images."
Step 6: Finishing up
After you've clicked "done with images," it will show you a preview of your posting. Scroll down to the bottom, and click "Publish." It will send you a confirmation email. Open the email and click the link. Your ad will be posted!
Step 7: Response
Once your ad is posted, wait to be contacted. I always have the Craigslist's way of contact, which is you'll get a Craigslist email from whoever is contacting you. Neither you or whoever is contacting you will get each other's email addresses, though you'll be communicating through email. If you would prefer a different way (call, text, or personal email), you will have to post that somewhere in the ad. I prefer to go through Craigslist only, for privacy reasons.
You may get only one, or several responses. You can do first come first serve (FCFS) or go by whoever looks like the best home. Some people will just ask if they're still available, and not go any further than that, so if you're FCFS, and someone comes along that is like that, you might miss out on a good home. If I've gotten several responses, I like to read through them, looking for whatever one that looks like they'll be the best fit. My top things are: Can they take all? How soon can they get them? It's easier for me if they can take them all and the sooner that they come, the better. Try to respond as soon as possible. When I have a Craigslist ad, I try to check my email at least once a day, but the more I check it the better. Sometimes, I'll get somebody responding that'll be only in the area for that day, and will try picking up that day.
Step 8: Once Re-Homed
Once re-homed, please delete as soon as possible! You can do this by going to your account and clicking delete posting under manage. By clicking "Delete," it will delete your posting immediately.
You can undelete your posting if you've accidently deleted it.
Once deleted, nobody will be able to see your post.
Scam:
On Craigslist, there is a lot of scam. Beware of this. You don't want to look like a scammer, and you don't want to deal with a scammer. If you are selling anything on Craigslist, you'll most likely get at least one scammer trying to contact you. If you don't want to look like a scammer on your ad, here's some tips: Post actual pictures of the roosters that you are re-homing. Do not post screenshots even if the screenshot is of your roosters! Do not post pictures from online, the pictures must be your pictures. Look over your ad before posting. If possible, make certain that everything is spelled correctly (chicken breeds will sometimes be marked as miss-spelled, even when they are spelled correctly). Began each sentence with a capital letter and use the correct punctuation. It's ok if you are not able all of this, but it does help if you do.
As far as scammers themselves, an often sign of a scammer is they'll try to get you to ship your roosters to them. They'll try to do money transactions not in person. (If money is involved, have the buyers pay you when they pick up the roosters, not before, not after.) That is what I've seen of scammers. There is other ways scammers work, but I'm not familiar with any other ways, and, if you are re-homing your roosters for free, you shouldn't have to worry about scammers. Scammers aren't very likely to go after free roosters, though that isn't a reason to let your guard down.
Also, if possible, have it as farm pick-up only. Don't ever do a transaction of any sort by yourself. Safety comes in numbers, so always have somebody around if somebody is doing a farm pick-up. If you are meeting somebody away from the farm (some of you may prefer to meet somewhere else than to have farm pick-up), make certain that somebody goes with you.
Extra:
You don't necessarily need to follow this article for just giving away roosters. You can use this for help on re-homing retired hens, or selling chickens or other livestock. If you are selling chickens, here is some average chicken prices:
Average layer, 4 months to 1.5 years: $15-$20
Average rooster, 4 months to 1.5 years: $5-$10
You don't need to sell them for that, but that's what they seem to be going for, so that's why I suggested those prices.
Once you've posted an ad on Craigslist, it can sometimes take up to 15 minutes for your new ad to pull up on a Craigslist search. I don't know why it takes that long, I just know that it sometimes will take that long.
All pictures/screenshots in this article is for an example, I created that Craigslist ad for the screenshots for this article, as soon as I was done, I deleted the ad. Any location or contact in this article is for an example, I didn't show my location (town) or contact on that ad. I used roosters José the Douglas White (That's something I bred, so aka barnyard mix), Duke the New Hampshire Red, and Beemer the TSC Silkie.
I hope that this article will help anybody who needs help on re-homing any chicken or any other livestock. Thanks for reading. 
~Lacy Duckwing
