DontRunMeOver

What I started off doing is learning chords on the piano and practising some scales. If you want to accompany yourself then having an idea of what each chord sounds like will help you to do everything instinctively - and freestyling in music is all about doing things instinctively. Get a basic knowledge of which keys on the piano play which note, find out which notes are used to make each chord and which key signature these chords fit into. Then you'll be in the position to just start playing around with your knowledge.

Usually, for solo piano the left hand plays the bassline and maybe a chord (like the rhythm section in a band) while the right hand plays more of the melody (like the lead section in a band), so what you're doing by learning chords is learning what to play with your left hand, so that you can bash out a melody with your right. For the right hand, it might be worth learning scales, but as long as you get used to the pitching of each note on the piano, you should be able to play the tune that is in your head without needing to know what scale it fits with.

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