Write on slides with the PowerPoint pen

When you're making a presentation using PowerPoint, you can circle, underline, draw arrows, or make other marks on slides with your mouse during your presentation to emphasize a point or show connections.
1. To mark up slides during a presentation During your slide show, right-click and point to Pointer Options.
Note: You must be in Slide Show view to see the Pointer Options command. To switch to the Slide Show view, on the View menu, click Slide Show.
2. Click a pen option. Hold your mouse button down as you write or draw on your slides. You can also use the Pointer Options command to choose a different color ink for the markup.
3.If you don't want to disrupt the continuity of your presentation by right-clicking and navigating through menus, you can use the keyboard shortcut CTRL+P to switch to using the pen and CTRL+U to revert back to the automatic pointer.
4. Your markings are erased automatically when you move to the next slide. To move to the next slide when you are using the pen, use the DOWN ARROW key.