How should you count music? The rhythm of music is something you feel. Maybe your body moves to the music or you tap your feet or clap your hands. Our words also have a rhythm to them, in poetry especially.
When practicing music, especially when you learn a piece, or if it is tricky, you may need to count the beats in order to keep your place in the music. But if you do need to count, you need to keep the counting and the music rhythmical as you do it. Either you need some other source of rhythm and count in time with that - or you need to make sure that your counting is itself rhythmical.
So depending on how you do it, you may find it easy or hard to count as you play. It is probably a bit more of a challenge to count along with the music if you count using words for instance, as that is a bit like trying to play two instruments at once.
Anyway the counting is an aid to learn the rhythm and find your place in the bar. It is important to be able to do it when you need to, But once you can feel the rhythm, you can drop the counting. You can just feel the positions of the beats in the bar if that is easier for you. You know where you are in the bar but you don't need to maintain a "running count" all the time.
You may feel the rhythm in your body or as visual movement
Many musicians find their body naturally moves slightly with the music as they play, and that can be a way to feel where you are in the bar for instance. Or maybe you think about your position in the bar visually as movement as you play - as a pointer perhaps, or conductor's baton, bouncing balls or whatever. If you do then that's absolutely fine.
You don't need to tap your feet along with the rhythm or anything obvious like that, though that does no harm either if it feels natural (and doesn't disturb others). It is a common way to keep in time in traditional music.
The rhythm needs to be the basic thing, your playing flows with the rhythm rather than the other way around
It is so easy to adjust the tapping to your playing, especially if playing something tricky such as a polyrhythm. The same is true for counting, moving your body, visual imagination or whatever, again it is so easy to adjust these methods to your playing when you reach a tricky passage, and then they become useless as a timing aid.
If you find you do this, then you need to make sure your counting is rhythmical and in time.
Instead of relying on the rhythm of your counting, foot taps or whatever, play along with a metronome that counts the beats for you. Or a conducting metronome which shows the beats to you visually. This is where Bounce Metronome Pro can help.
If you find counting distracts you, this lets you drop that, listen to your playing, and let the conducting metronome keep count for you. Also you no longer need to worry that your counting will adjust to your playing rather than the other way around.
This lets you focus all your attention on the main thing, which is to feel the rhythm and to keep exactly in time with the beats.
When the rhythm is internalised, drop use of the conducting metronome
Then once you feel the rhythm of the piece, you can drop the use of the conducting metronome as a way of keeping count of the beats within the bar. It's just a way to help you to feel the rhythm, it's not an end in itself.
Though you can usefully keep returning it to hone your ability to play exactly on the beat (when you want to that is). That's something one can continue to work on even when one can feel the rhythm perfectly - perhaps eventually to within a millisecond or two if you need to - see How to refine your timing .