How Do You Get Over the Initial Fear of Sounding?

I was always curious about sounding, but the idea of sticking something inside my urethra freaked me out at first. The game-changer for me was using lots of sterile lube and going way slower than I thought I needed to. The first few times, I barely inserted it, just letting my body adjust to the feeling instead of forcing it. Once I got past the mental block, it became insanely pleasurable. But I still get nervous trying bigger sizes. How did you get over the fear and fully enjoy the experience?