You can imagine any number of approaches to an arpeggio that will nudge it along to fluidity. One, is thinking that the elbows, arms, and wrists are playing the fingers. In a sense the fingers are the end of a total arm suspension. Relaxation is the key word.
The C# minor arpeggio is thankfully symmetrical and starts with parallel fingers 2, 1, in both hands and then progresses through reciprocal (or mirror fingers) on the G#, C#: The Right hand uses 2, 4, while the Left is in reverse, with 4,2. Thumbs MEET between these black key tunnels. Such a predictable pattern of notes assists the student on a cognitive level.
C# E G# C# E G# C# E G# C#
The Physical or Kinesthetic dimension of arpeggio playing:
The videotaped instruction fleshes out a swing of the elbows, and demonstrates how a student can practice sweeping, curved motions of the arm SILENTLY before infusing sound. The miming of movements is one of the ways a player can be his own best coach between lessons.
Blocking is another technique reviewed in the footage.
Finally, thinking of arpeggios as playful romps over the keys, with abounding rolls of energy is a great frame of reference. It applies to legato and staccato playing since both need contouring.
Practicing the E Major Arpeggio
POWHOW LIVE webcast piano instruction: