In order to achieve speed and evenness, both vital for later development, you must practice alternating right hand finger combinations in scale and single line melodies. Each of the exercises to follow should be played first with im, then ma, then ia.
A very important aspect of right hand finger action during rest stroke passages is for the fingers to perform a walking motion. As i plucks, m is close to the string and ready to strike. As i springs away after resting on the adjacent string (previously explained) m proceeds to strike while i waits to start over again. Used continuously this sets up the 'walking' action known as alternation.