C major scale
practice this scale a few times as a warm up. Make sure to press down with the fingertips and try not to bunch up your fingers
practice in groups of four bars, trying to get each group perfectly three times in a row. Use a metronome tempo of around 48 (Ho slower if need be)
read the rest of twinkle little star for practice.
work on the checked chords. For the more difficult chords, just play the first three strings of the chord.