You should use PTFE (polytetrafluoroethylene) plumber's tape, also known as thread seal tape. It creates a watertight seal, prevents leaks, and lubricates the threads, making it easier to tighten without overtightening. Wrap it clockwise around the threads 3-5 times before screwing on the new spigot, ensuring full coverage.

First, ensure the water supply is completely off. If the spigot is stuck, try applying a penetrating oil to the threads and let it sit for 10-15 minutes to help loosen corrosion. For stubborn fixtures, a pipe wrench might provide more leverage than an adjustable wrench, but always be careful not to damage the piping within the wall.

Turning off the water supply is absolutely critical; skipping this step will result in a significant and immediate flood once you begin removing the old spigot. Always locate and turn off the dedicated shower shut-off valves first, or the main house water supply if none are available for the shower. Failure to do so can cause extensive water damage and make the project impossible to complete safely.

This project is rated beginner because it primarily involves basic tools and straightforward steps of unscrewing and re-screwing. However, it requires careful attention to detail, especially with water shut-off and leak testing. If you're comfortable with basic mechanical tasks and following instructions, you can successfully tackle it, but don't hesitate to call a professional if you encounter unexpected issues or feel unsure.