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You can use the Bookmark tool to create links to specific spots in your document. This is great for tables of contents, glossaries, and citations. You can highlight a portion of text, select an image, or just place your cursor in the spot you want. You'll find this in the "Links" section. Make sure the name is descriptive enough that you'll be able to recognize it. This is especially important if you are using a lot of bookmarks or more than one person is editing the document. Bookmark names have to start with a letter but they can contain numbers. You can't use spaces, but you can use underscores instead (e.g. "Chapter_1"). Bookmarks will be surrounded by brackets. These aren't displayed by default in newer versions of Word. To display bookmarks, click the File tab, select "Options," then click "Advanced." Scroll down to the "Show document content" section and check the "Show bookmarks" box. Highlight the text or click the image that you want to turn into the hyperlink to your bookmark. This will open the "Insert Hyperlink" window. You'll see a navigation tree with your heading styles and bookmarks. Expand the "Bookmarks" tree if it isn't already and select the bookmark you want to link to. You can also select from heading styles you've applied throughout the document. You can test it after inserting it by holding Ctrl/⌘ Cmd and clicking it. Your document should scroll to the bookmark's location.

Summary:
Place your cursor in the spot in the document you want to link to. Click the Insert tab and select "Bookmark." Give the bookmark a name. Click "Add" to insert the bookmark. Select the text or image you want to create the link from. Click the "Hyperlink" button in the Insert tab. Select the "Place in This Document" option in the left menu. Select the bookmark you want to link to. Click "OK" to insert the link.