Consider how many contact numbers you have. Craigslist's account creation will require a valid phone number. Once the sign up process is completed, you will then receive a phone call or a text message for the validation code.
Create different email accounts. Let's say you have access to 10 different phone numbers; you will still need to create 10 different email accounts for your ads. Once you've created 10 different email accounts, you're ready to post your ad 10 times.
Go to Craigslist.com to create 10 accounts. Click on "My Account" on the upper left-hand side. You will then be directed to a page where you can log in. Under the boxes, click on "Don't Have An Account" to sign up.
Enter your email address and key in the verification word. It will eventually require you to put your phone number in. Once you put the phone number in, you will get either a text message or a phone call with the validation code. You need to enter that code into Craigslist to create a valid account.
Set up your ads. Always remember not to post the exact same ad more than once, including your headline. Duplicate posts are prohibited on Craigslist. Be creative and try to write different variations of the same ad. A common strategy is to include a bunch of numbers, letters and symbols within the headline. For instance, if your ad reads "Cute Boston Terriers," you can alter it like "#@#_Cute Boston Terriers_#@#" or "Cute Boston Terriers______W8H8P7."
Repeat the posting process 10 times. Always remember you will need to check each email account to activate each individual valid account.