Having written last about tooth brushing, this would be a good time for a few words about flossing and flossing techniques. Flossing is just as important as brushing, maybe more so. Toothbrushes do not clean effectively between the teeth. They only clean well on the smooth outer and inner surface of each tooth. Even electric toothbrushes, including those with a water spray, do not clean thoroughly between the teeth. On the other hand, floss is designed to clean the hard-to-reach area between the teeth, which, coincidentally, is a natural hiding place for bacteria (plaque) and food.
So to clean the area between the teeth well, one must supplement brushing with the use of floss or an interproximal brush, provided there's enough space between the teeth for it to fit without causing harm. The nice thing about floss is that it will generally fit anywhere, no matter how close together the teeth are.
It doesn't matter whether you floss in the morning or evening, just as long as you do it at least once a day. If the morning is better for your schedule, then that's fine. That's when I do it because I know, late in the day, I'll be busy or tired, so it won't get done. Of course, more than once a day is even better.
Flossing or using an interproximal brush is not just about removing food particles between the teeth, though that is certainly important. It's about rubbing up and down on the side of the tooth (every space has two sides where the teeth meet) to remove the film of bacteria (plaque) that is growing.
You won't see or feel the bacteria coming off the way you do with food particles - they're too small to be seen without a microscope. If you feel and hear the floss rubbing up and down a few times on the side of each tooth, then that is the only feedback you'll get that you have done an effective job.
Flossing is a little more difficult if you have cemented bridges, that is, multiple teeth joined together as one. Then you have to use a "threader" to pass the floss between each pair of teeth. But, they need to be flossed just as much as freestanding teeth - the bacteria don't discriminate. To make matters worse, all bridges and all dental fillings and restorations have margins where they meet the teeth. These margins have small spaces that must be kept clean. If they are not kept clean with floss and toothbrush, decay may develop, and then the entire filling or bridge may have to be replaced. Who wants that?
So make flossing a daily habit just like you do with brushing and enjoy your healthy, clean teeth.