The goal of the ten second meditation is to be mindless. Try and disengage with your mind’s internal chatter. Being mindless requires you to observe your thoughts without giving into them.
If you find yourself second guessing the ‘correctness’ of your meditation, you may be attempting too much, too fast.
Think of your ability to meditate as building muscle. It’s done methodically, and builds over an extended period of time.
Try it now, it’ll only take 10 seconds:
Breathe - Start building your meditation practice with a single deep inhale, filling your belly; then exhale at the same pace. On average, one complete breath takes roughly 10 seconds to complete.
Observe thoughts - At first you may notice your mind to be full of thoughts. Observe these thoughts but continue to complete your breath. Overtime you will notice the mental chatter to slowly fade away.
Piggyback Habits - Pick something you do everyday and use that habit as an anchor to practice meditation. Perhaps it’s before you brush your teeth, shower, start your car, walk into work or go to the gym. Find something you do daily, and anchor a single deep breath to it. Repeat daily.
Increase slowly - Once you can consistently anchor a deep breath to an existing habit, add the meditation to other habits. If you have a thought that reminds you of your meditation practice - use that as a cue, and do the 10 second mindless meditation.