Which keystroke shortcut should you use to display all worksheet formulas instantly?

To display all worksheet formulas instantly in Excel, you should use the keystroke shortcut Ctrl + ` (the key usually located to the left of the number 1 on your keyboard). Here are the steps:

1. Open your Excel worksheet.
2. Make sure the cell or range of cells for which you want to display the formulas is selected.
3. Press and hold the "Ctrl" key on your keyboard.
4. While holding down the "Ctrl" key, press the "`" key (usually located to the left of the number 1 on your keyboard).
5. Release both keys.

Now, all the formulas in your worksheet should be displayed instead of the results they produce. To switch back to viewing the results, simply repeat the process.