In practicing a piece for performance, it is very important that a player is prepared enough so that a piece can be played with confidence and enjoyment. The first and most most important aspect of performance preparation is complete confidence in the notes.

Here are some piano practicing tips that will gain note confidence and overcome performance anxiety.

Slow Repetitions With the Metronome
Play through the piece very slowly, with the metronome, without the score. Set the metronome at a very comfortable tempo, make sure that the tempo is slow enough that no notes are missed. There should be no struggle nor scrambling to play the notes. The notes should not be pounded to keep beat with the metronome. The focus should be on the metronome pulse, then the notes will start to flow without effort. This takes some practice, and it may take several attempts to get the tempo right. Set the metronome to different pulses, start at one click to a quarter note, then one click to a half, then one click to a bar. There are many possible variations to try, all will help with note confidence.Repeat the piece numerous times. Stand up and stretch out the arms often during practice sessions. Keep the pulse from the metronome the most important focus. If some notes are missed, just keep going in time with the beat.

Try Playing With Eyes Closed.
Even large leaps can be played correctly without looking, but this takes practice! If a piece can be played comfortably without looking at the score or the hands, the piece will be very much easier to play in performance. The goal is to have the notes completely automatic, there should be no need to consciously think of notes when performing

Make Recordings of the Piece
Listen for any places where the notes sound insecure or poorly articulated, those sections need more slow practice, maybe the tempo needs to be slowed down further and small sections repeated. Practice in musical sections when working on small parts of a piece, never chop a phrase into a fragment. After repeating a small number of phrases, add to the section to gain more confidence in the context of the piece.

Going through the score for details
After practicing without the score for a while, it is important to go back and review the written notes. Make sure that all dynamic markings are observed, and that there is enough dynamic contrast within the piece. Are the Piano markings sounding softer than the Forte markings? Are the articulation marking observed? Make sure that the tone is matched, especially within phrases. If there is a held note within a phrase, the following note needs to be played softer, because the held note's tone has diminished.

As soon as a piece is memorized, perform it as often as possible, on different pianos.

Schedule at least a week to take a break and not play the piece at all. Returning to the piece will bring new insights.

The most important part of musical preparation is careful, slow practice, which will ensure that bad habits do not intrude into the playing. Even as details of interpretation are worked out, slow practice should be continued. As note confidence improves, the interpretive details will shine.

No matter what the distraction from nerves during performance, if properly prepared, the notes will play themselves, and the performer can concentrate on making music.