This video shows a child singing the Solfa major scale at 60 bpm with a double time scale following.
This video shows a Solfa major ascending and descending scale on D (singing) at 60 bpm, with double time, 3x.
This video shows “I Am Like an Apple Seed” played pizzicato on D at 60 bpm.
This video shows 10x playing do, re on D with a “lift, place” after each set. Start practicing this exercise as slowly as you need to do each step clearly and carefully. Then work up to this speed.