Practise every day. Check your technique. Are you playing with relaxed wrists and curved fingers? Is the piano stool set up correctly? Make sure you have good lighting when practising. Practise slowly, hands separately (this is how advanced pianists practise too!) Do not try to ‘run before you can walk’. Make sure you have got the basics right before moving on. Strive for perfection. Listen for the melody. Identify where the melody is. It might not be in the right hand; it could be in the left or alternate between the two. It could be that you have to ‘voice' or pick out the melody whilst playing non-melody notes in the same hand. As a beginner, always use the suggested fingering in the book or the fingering suggested by your teacher and stick to it. I cannot stress how important it is to learn the correct fingering from the very beginning. Do not forget to count.