While creating your product catalog if a General / Occasion template catches your eye, then you can save it as My Templates.
This way you can customize the template to match your brand colors, or add your logo, and use it in future.
Here's how you can do that:
1. On the Select Template screen choose one from General or Occassion and click Next.
2. Select Master Templates and then click on Edit under any one of the variations.
3. This will take you inside Designer. Here you can edit your template (font / colors / background etc) and then click on Done.
Now it's part of your personal library of catalog templates!