A chromatic scale proceeds by half tones.
To play a chromatic run a finger must frequently move higher or lower to produce a difference of a half tone.
This demands much careful practice and must be done like other work, in sections.
Begin by playing the 1st 2 notes only. Play F and F#.
To how yourself where the 2nd finger must be placed to play F#, you may play it once with the third finger placing that finger as close to the 2nd as it is possible to do; after having heard this sound, slip the 2nd finger up sufficiently to have it take the place of the third finger and produce the same sound. To play a correct F#, the 2nd finger must be placed exactly where the 3rd finger would be if placed on the string as described above.
Move the 2nd finger with a firm pressure and deliberate movement to F#. Then play G with the 3d finger and proceed in the manner explained to play G#.
It is more difficult yet to draw a finger back to play a note which is a half tone lower. It is always more difficult to play toward runs with correct intonation which means to place the finger-tip at the correct place.
Play first by raising the finger and afterwards without leaving the string.
If you will practice in this manner daily for at least 15 minutes you will soon notice an increase in strength and accuracy.
Pieces and studies written in keys with flats are more difficult in execution than those with sharps. Give them more time.
The violinist should always have the piano accompaniment as no professional musician will "fake" an accompaniment unless it be fore some easy popular melody and bear in mind, when professional condescend to do so they generally have played the piece before.
It is self-understood that some have the natural gift to make an accompaniment that will answer.
N.B. When writing always mention instrument. Confine your questions to ONE LESSON ONLY. Give name of lesson, number of staff, number of measure, and be brief. Give full name and address.