How do you add a white border to a picture on Snapseed?

Based on the provided reference, Snapseed allows you to add a border to your pictures, and you can customize this border, including adding text to it. Here's how you would achieve the effect described in the referenced text:

1. Open your image in Snapseed.
2. Use the tools available to add a border. (The reference doesn't specify the exact tool, but explore the editing options.)
3. Add text to the border, which in the video example, the user inputs "mr geek."
4. Position the text within the border.
5. Confirm the changes by tapping the checkmark.
6. Export the image.

The reference doesn't give specific steps on how to make the border white. Thus I can not answer the question specifically.