Open Up an Article
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Go to Administrator >> Content >> Article Manager and open up any long article.
Put Your Cursor in the Text
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Place your cursor in the text at the point where you want the pages to split.
Click Pagebreak
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Scroll to the bottom of the page and click "Pagebreak".
Give the New Page a Title
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Select a title for your new page and click "Insert Page Break". The second field called "Table of Contents Alias" will be the URL for this second page.
Repeat the Process
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Keep clicking "Pagebreak" until you have split this article as many times as you wish. Each time you do, you should see a grey line across the page. When you're finished, click "Save".
Visit the Article
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Now when you visit the article on the front of your site you should see two special items:
1) "Article Index" which serves as a table of contents to the article pages
2) Prev and Next buttons at the bottom of the article for people to move on to the next page