Everybody knows that you should hold a golf club lightly. As Harvey Penick said, Arnold Palmer does not hold the club lightly, but you are not Arnold Palmer.
But still, I don’t think you should of hold the club lightly.
Instead, I think you should hold the club softly. That word describes how the handle should press against the fleshly pads of your palm and your fingers when you enclose them around it. Softly.
I don’t really know what a light grip feels like. But I know when the handle feels soft in my hands, yet secure, and so do you. Use that kind of grip and see what you get.