Figure out a website you yourself would like to manage as a business or hobby. Choose something just complex enough to show off your skills ... but not something so ambitious that it would eat up all your time.

Then pick the best domain name for the project you can reasonably afford, and get started. This will be good practice – not only for the sake of honing your dev skills, but also for understanding the challenges of designing a website, furnishing content, attracting customers / readers, monetizing traffic, and so forth.

These are the very challenges your employers or clients will be facing. If you understand their perspective, then this helps you help them; and it helps them trust you to help.