In a copy of the presentation, choose Design, Slide Size, then Widescreen (16:9). If PowerPoint asks how to scale your content, choose Ensure Fit on Windows and review the layout before presenting.
Make a slide that exposes layout problems
Use a Standard (4:3) slide with a photo across the middle, a narrow text box near the right edge and a small footer near the bottom. Save a copy before changing the deck. The size change affects every slide in the file. Record where the edges of the photo and footer start so you have something concrete to compare.
Fix the wide layout slide by slide
Check that the footer is visible and that the right text box still wraps at readable points. Reposition the boxes to use the wider canvas. Crop photos to fit their new frames when needed and keep important parts of the image in view. Check repeated elements on slides that use different layouts. Run Slide Show at full screen to spot text that looks acceptable at editing zoom but is too small from across the room.
Version and exercise
These instructions target PowerPoint for Microsoft 365 on Windows. On Mac the scaling prompt can use different wording, including Scale. Try the same conversion on a duplicate with Maximize on Windows. Which slide element needs attention first?
