Players often complicate their service actions to try and hit more aggressive serves, but really the key is to keep the serve simple. The best serve is consistent and accurate. Some slice on the shot will keep the ball low and a medium fast speed will make it difficult to return. The higher the level, the more accurate the serves need to be, but also the better the opponents are likely to be at returning.
Players should practice getting the right slice on the ball, with simple technique, before they try to hit the ball too hard. Accuracy is more important than speed. In tennis, players take baskets of balls to practice their serve, but in padel, players do not practice because they feel the technique is so simple. But actually, like tennis, it is the one shot a player has complete control over and is a great opportunity to start the point in an advantageous position.
Key: PRACTICE, PRACTICE, PRACTICE