When you print, you'll need to make sure that "Scale to fit paper" remains unchecked. There may be a few other tricks to get what you want but let's start with that and not try to Shapes will land where you put them, but PPT will snap them to the edges of the slide so it'll be fairly simple to ensure that they land where you want them to.
The next step would be to define a custom page size that's A4 dimensions less 20mm in both directions (10 mm border on each side). In all probability, the margin will be a bit less than 1cm, in which case you can do what you're after. That'll tell you how close to the edge your printer is physically capable of printing. The resulting page will likely have an unprinted margin. Next, click the Apple icon in the menu bar and select System Preferences from the drop-down menu. Alternatively, select the 'Songbooks' style level in the toolbar at the top left. Click on the 'Songbooks' button, located to the left of the 'Bibles' button. On your Mac, quit any Office applications that are currently running. Any song verse will do, this is just so that you can edit the margins. Change PowerPoint’s Measurement Unit on Mac. That will cause PPT to send the slide out to the printerĪt full size, not scaled down to accommodate the printer's margins. The next time you open PowerPoint, the measurement units will have changed to the selected measurement system. Print it, making sure to REMOVE the check next to "Scale to fit paper". Create a slide that's nothing but a colored background. Set the page size to A4, assuming that's what you'll be printing on.
Vinay has explained how to set a custom page size. PowerPoint doesn't have margins as such, and at least in part the margins you get when you print are dependant on your printer very few printers can print clear to the edge of the page.