Sing major scales and chromatic scales repetitively. Start by singing the scales abnormally slow, accentuating the sound of each note. Don’t worry about how smooth your transition is between notes yet, as long as each note is distinct. Practice doing this for about 10 to 20 minutes each day, rather than practicing for long periods every once in awhile. The goal is to be consistent and achieve muscle memory in your throat for each note.
Blend the notes more smoothly once you’ve achieved muscle memory for each note. Focus on merging the sounds in the transition period by softly shifting the shape you make with your mouth as you produce vowel sounds. Notice the way each note vibrates differently in your throat and sounds in your ears as you practice blending.
Listen to examples of correct blending. A voice recording, a vocal teacher or a musician blending properly with an instrument can demonstrate correct blending. Compare similarities and differences between yourself and the teacher. Repeat the exercise again.
Increase the range and tempo of the exercises in the previous steps as you become more accurate. Increasing the range and tempo before mastering this exercise for basic scales will slow your progress by confusing your muscles.
Sing head- and chest-dominant tones. Sing solely from the head first for a minute. Stop and rest. Sing solely from the chest for a minute. Notice the feeling and sound differences.
Find a “gray area” between the head and the chest. Begin to make a head-dominant sound, and attempt to blend that with a chest sound. This feels awkward for a while, but becomes simpler in time. When you hit a middle sound, hold it for as long as possible, and attempt to make that exact noise again after resting.
Transition from a head sound, to a middle range sound, to a chest sound. Make this transition as gradual as possible several times. With each repetition, the transition becomes smoother and more pleasant to the ear.
Record yourself on each of the exercises when you become comfortable. Start with the scale exercises and move to the tone exercises. Listen to the recordings and repeat. Continue to practice for a few minutes each day rather than for hours every once in awhile.