One interval that you need absolutely have in your ear and to begin with is the half step. You have probably heard the famous theme from the movie JAWS. Listen to the cellos playing E and F again and again. Play and sing each interval slowly.
Half-step/ Minor second Intervals
C to B Descending:
E to F Ascending:
Major Seconds / Whole-Steps Intervals:
C to Bb Descending:
Singing "Happy Birthday" is a great way to remember the sound of the major second. Listen to the three first notes of Toots Thielemans ' interpretation.