Watercolor paper is THICK and you usually need a background light source to trace line art onto it before you begin painting. And for calligraphers, it's often helpful to first TRACE your letters before trying them out on your own. A light pad or light box is an easier alternative to using a window. Watch this review of three different light pads to see which one is right for you!
Mentioned in this video:
// Huion Ultrathin Portable A4 Lightbox: https://amzn.to/3k4Sa7d
// Tikteck Ultrathin Portable A4 LED Light Pad: https://amzn.to/3srUWau
// (Similar) Cricut Bright Pad Go: https://amzn.to/3z0TeiU