To play one note at the time
It is important to learn how to play one note at the time. There are several methods, you can try which one you like the most. It is good to master more than one of below since you can use them for different effects, there are also other ways to reach the objective of only playing in one whole.
The underlip method
Fold the underlip around just one whole. If you leant he harp in an angle upwards it is not so difficult to perform.
I personally prefer this method when playing. It keeps the thungue free, so you kan perform T-sounds (both when blowing and sucking) which gives you an excellent precise rythm. Remember: Playing well is all about rythm!
The "U-tungue" method
Form a U with your tungue and circle it around just one whole on the harp. Using the toungue is fast when you want to shift notes fast. Not all people are able to curl their tungue this way. This is a matter of genetics, but most people can do it.
The Toungue metod
With the Tungue method, you cover the wholes with the tongue, but allows one whole to be open to the right. By occationally lifting the tongue from the harp, you may accompany yourself with a chord This can be a very nice effect especially when playing the waltx.
Since the harmonica is tuned in chords. You have the basic (tonic) chord when blowing. You can use this technique to accompany yourself by removing the thoung in a rytmical fasion. This can be very effectiv especieally when playing folk tunes.
Kissing method
Vertical method
By holding the harp vertical you may isolate just one note
