What is the first step to create an outline in Excel?

To create an outline in Excel, the first step involves using the grouping feature found under the Data tab, specifically the option for Auto Outline. This allows you to organize the data effectively by grouping related rows or columns together, thereby enabling the expansion and collapsing of details which makes it easier to analyze large datasets.

When data is grouped, Excel can automatically generate an outline based on the structure of your data and any subtotals you might have included. This enhances data visualization and improves navigation through more complex spreadsheets by allowing users to view summarized information at a glance.

The other options indicate actions that do not lead to creating an outline. Sorting data is important for organization but does not deal with grouping. Filtering data helps in viewing specific information but does not establish an outline structure. Lastly, while there is a feature called Create under the Outline menu, the direct and functional approach to automatically generate outlines is through the Group option.