One of the quick way to customize SharePoint online navigation is to use the Edit option available at the top bar.  Recently, Microsoft has also introduced the drag and drop functionality to edit the navigation.

Prerequisite

1. Site owner permissions required.

2. If you are not site owner, make sure you have permissions to modify the navigation.

How to customize SharePoint Online top bar navigation

1. Go to your SharePoint online site.

2. On top link bar, click Edit Links

SharePoint Online navigation

3. Click +Link to add a link e.g. a document library link

SharePoint Online navigation 2

4. Type text and URL address of the library. You may

use Try Link option to check the URL validity.

SharePoint Online navigation 3

5. Click OK to save the link.

6. Click Save button to finish the top navigation bar editing.

SharePoint Online navigation 4

7. Now you should be able to use the link to access the document library.

SharePoint Online navigation 5

How To customize side navigation bar using Drag and Drop

Let’s try to add a link to a document in a side navigation bar by using drag and drop functionality.

1. Open the document library.

2. Click on Edit links on the side navigation bar.

SharePoint Online navigation 6

3. Click on the document and drag it to the side navigation bar.

SharePoint Online navigation 7

4. Drop the grabbed document to the place you want to display the link.

5. You can drop the link at any position of the side navigation bar.

6. You may also change the existing links positions.

7. Click on X icon to remove any link from the side navigation bar.

8. When you are done, click Save button.

9. Your updated side navigation bar is ready!