With oscillating (rotates back and forth) or sonic (vibrates fast), you use them the same way. You angle it towards the gum at 45degrees upwards for top teeth, downwards for bottom teeth. So, it is on the tooth but angles towards the gum as it’s where the tooth and gum meet that needs the most attention.

Do it in a particular order. Best way is start on outside top right, work slowly around the outside to the top left and then return on the inside. Do the same on the bottom. Some brushes will have paused or beeps every 30 seconds to help you time this.

The brush should not be pressed firmly, but just gently applied to the teeth and the motion of the sweeping does the cleaning.

Ar the end, clean all the biting surfaces of the teeth too for an additional 30 seconds.

This is called the bass technique. Using a manual brush you do the same thing, but you have to make the little circles yourself, which is trickier to do effectively.

You can verify you are doing it well with disclosing tablets. They are tablets that stain plaque, usually red or pink or blue. After you brush, you chew or suck on one. Then you can see if you’ve missed anywhere. They are not designed to be used every time but every day for a few days or weeks until you are confident you get everything. They just show you what you missed.

Try with a manual one day and an electric the next.