When you play the piano, your hands need to be rounded and relaxed. Try holding a ball or placing your hands on your kneecaps. Notice how your fingers gently curve, and practice keeping your fingers in that shape. When your fingers curve in a proper hand shape for piano, they shouldn’t be bent or tense. You should be able to see all 3 knuckles on each finger. Keep your wrists relaxed as well. on a tabletop. Work on your finger coordination by playing scales on a table as if it were an actual piano. As you ascend a scale with your right hand, practice crossing your thumb to play a scale’s fourth note. Then descend the scale and practice crossing your middle finger to play the sixth note. As you ascend a scale with your left hand, cross your middle finger to play the sixth note. When descending with your left hand, play the third note with your thumb. Starting with your thumb and ending with your pinky, tap all 5 fingers as if you were tapping the keys from middle C to G. Tap extra hard every third tap to create an accent rhythm. Ascend and descend, or tap from your thumb to your pinky, then from your pink to your thumb. Tap as fast as you can while keeping the accent rhythm. Switch up the intervals you accent and add combinations, such as accenting every second and fourth taps. Number your fingers 1 through 5 from your thumb to your pinky. Pick a combination of numbers, such as 1, 2, and 5. Practice tapping with your thumb, index finger, and pinky in that order. Switch up your combinations and make them more complex. Try tapping as fast as you without making any mistakes. Practicing scales and drills with your non-dominant hand can help you improve your coordination and dexterity. In addition to practicing, you could try brushing your teeth, combing your hair, and performing other tasks with your non-dominant hand. You can practice playing a piece on a tabletop either from a score or by memory. Try to imagine playing it as vividly as possible. Do your best to hear every note and feel your fingers strike the...

TL;DR in Indonesian:
Berlatihlah bentuk tangan yang benar. Berlatihlah skala tangga nada pada permukaan meja. Lakukan senam ritme jari. Cobalah ketukan kombinasi. Luangkan waktu lebih lama melatih tangan yang tidak dominan. Mainkan satu lagu pada permukaan meja seakan-akan itu adalah piano. Berlatih menggunakan video panduan daring.