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Once you are satisfied with their order, click "Combine," and Adobe will generate a single PDF file using these documents.
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Arranging your Contents
Once you have files assembled into a PDF file, you can rearrange them in several ways. Click the "Organize Pages" icon on the right toolbar. (Or, click Tools → Organize Pages.)
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Rotate pages by clicking on the page to highlight it. A small menu appears; click the circle-arrow icons to rotate the page image in either direction.
Organization via Bookmarks and Thumbnails
You may stop at the above step, if you're happy with what you have: a set of various documents combined into one PDF File. Plus, Adobe may have done a few things automatically that serve your purposes, too, by creating a system of organization:
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If you plan to add front matter to your document that is not paginated, you may wish to wait until that's done before creating page numbers.
Editing the Bookmarks List
In most cases Acrobat will auto-generate a set of bookmarks when you combine the files. File names will be the major headings, but there may be additional sub-headings, for example generated from the headings within the files, or individual slides in a slidedeck.
If you right-click on a bookmark, you get a variety of different options, including to delete or change it's destination (where it goes when a reader clicks it.) Probably most useful is "rename," since you may want more descriptive headings than your file names.
You can also manually add bookmarks:
Table of Contents
You may wish to go a step further, and create a Table of Contents as featured on a page or pages, presumably at the beginning of your PDF file. Although not a toolset built into Acrobat, you can create a dedicated Table of Contents that includes just page numbers, or are actively linked to your content. Unlike Bookmarks, the Table of Contents is a page within your portfolio, wherein the items in the Table list are hyperlinked to pages within the PDF. When your readers click on items in the table of contents, they are taken to the corresponding page. This presents a professional-looking product, and offers the option to create a document that is easily navigated if printed out, too.
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Create a set of pages in an MS Word file that are section headings or starters. Then, use MS Word's Table of Contents feature to auto-build the Table of Contents, which are links to each of the section pages. Add this file to your PDF file. Lastly, move the section pages to their appropriate places in the document, so that the Table of Contents created in Word helps readers navigate to the different parts of your PDF file. This second option is best when you need to compose opening remarks for each section of your file.
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