First, create a Signup box using Constant Contact
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To get started with your Signup box, watch a quick and informative Site Visitor Signup box video tutorial from Constant Contact on how to do so in your account.

After you have copied your script and are ready to promote your newsletter, then...
1. Visit: Static FBML for Facebook
"Add advanced functionality to your Page using the Facebook Static FBML application. This application will add a box to your Page in which you can render HTML or FBML (Facebook Markup Language) for enhanced Page customization."

2. Click on "Add to my Page"
Visit your page and click on 'Edit Page.' FBML will be listed under Applications. Click the 'Edit' Pencil and then click 'Edit.'

3. Give your box a title.
Let your fans know that they can sign up for your news letter in your title. Explain the benefts- keep it short and approachable. Paste your script from Constant Contact in the box below- FBML and click 'Save Changes.'

4. Go to the 'Boxes' Tab and click on the 'Edit' pencil and then click on 'Move to Wall tab'
Your newsletter signup box is now when your fans can easily see it.