If you want to use a template you've saved for your next presentation, here's how.
Add your template to the right Templates folder for ease of access
Copy or save your template (.potx) file to the Templates folder at:
C:\Users\ YourUserName \Documents\Custom Office Templates\
Tip: YourUserName isn't the literal name of the folder. It is a placeholder for your user name.
On the File tab, click New.
Select Personal or Custom. (The name varies, depending on circumstance.)
Under the tab you've selected, select the folder where your template is stored.
Double-click your template.
A new presentation opens with your template applied to it.
Set your template as a default option
You can mark your personal template to be an option on the default Featured tab. Here’s how:
Repeat steps 1–4 above.
Right-click your template and select Pin to List.