Cello Online Courses

How should my practicing be structured? Let’s say, four hours.

Being a student you should simply take my (half humorous) remark literally. Just practice scales with all possible variations for at least one hour a day, then spend another hour on other basics like double-stops, arpeggios etc. Finally dedicate a third hour on demanding etudes (Popper, Piatti, Grützmacher II) and then you may proceed to your beloved pieces of music whatever these might be now.