How should one prepare one’s mouth for Passover given that it starts on Saturday and one is unlikely to brush thoroughly on Shabbat?
After the meal before the end of the forth hour one should rinse your mouth out well. You can floss your teeth, if your teeth aren’t sensitive, which will cause them to bleed. If you are using floss from a roll, separate it before shabbos. Regarding brushing your teeth, we cannot use toothpaste on Shabbos, but if you have a liquid toothpaste, you can rub some of it on your teeth and then brush them. Don’t wash toothbrush off afterwards, and should be put away with chometz. You can also use a kosher for Passover mouthwash.