Tell us about yourself!
After smearing the inside of your swim mask with the toothpaste by using your finger, buff it off with a soft clean cloth. It must be paste, not gel, toothpaste.
By buffing the glass, any residue or 'gas' is removed. As to non-minty, do research for a homemade recipe.
To 'spill' a knot is to change its form and rearrange its parts, usually by pulling on specific ends in certain ways.