Focus on using a continental grip, turning your body sideways (shoulder to the glass), initiating power from your hip, lengthening your swing, and potentially using a racket with a softer core and larger sweet spot.
Sven offers some really practical advice here for players coming from other sports. If you're finding it tough to generate power on your smash, especially if you haven't played tennis before, this covers the fundamentals you need to understand. He explains how changing your grip and body movement can make a big difference, and even touches on how your racket choice impacts power. It's all about building a more efficient swing rather than just muscling the ball.