Learn the notes on the staff first -- starting from the bottom line and ascending, the notes on each line are: E, G, B, D, F. The notes on the spaces between the lines (also in ascending order) are: F, A, C, E. New students frequently use a mnemonic to memorize these notes -- for the notes on the lines: Every Good Boy Does Fine. The notes on the spaces are even easier to remember as it spells out the word face.
Learn the notes below and above the staff. Although the lowest note on the lined staff is E, there are notes that go below the lined staff, reaching the lowest note possible at the G. Beginners should learn the three notes above the staff.
Understand what the symbols on the sheet music represent - notes, rhythm, volume, tempo, silence and repeats. Learn to distinguish between whole notes, half notes, quarter notes, eight notes and sixteenth notes.
Learn the notes on the violin - the open strings are, starting with the lowest string, G, D, A, E. On each string, there are three notes between each open string. On the G, the notes are A, B, and C. On the D, they are E, F and G. On the A, the notes are B, C and D. On the E, they are F, G, A and B.
Practice playing the notes written on the sheet music on your violin. Begin with scales - this will help you concentrate on associating the notes on the sheet with the notes that you are playing. Play long notes at first and focus on memorizing where the notes on the sheet are on the violin.