I will assume incredimail is like any other email client.
You would set it up to access your POP email address.
You will need to enter your email address, your incoming mail server for POP (mail.yourdomain.ext), your outgoing mail server for SMTP (mail.yourdomain.ext) and you will have to tell it to authenticate you so you can retreive or send email. You do that by telling it to login using the email address you create and password that you set for the account.
Depending on your ISP you may have to tell the mail program to use port 26 for outgoing mail instead of 25.