Go to advertiser registration page and complete the registration content. A confirmation email will be sent, and then you will be able to login to begin using your account.
There will be no charge for having an advertiser's account. The only cost is for impressions of your advertisements.
Both the banner and the sidebar advertisements together are a penny a simultaneous impression.
YouTube videos having the word "watch" in the URL will not work. The proper pattern is https://www.youtube.com/embed/(video id).