Spirobel creates Monero testnet tutorial video
Spirobel1 has created a tutorial video2 in which he is setting up a local testnet3 for Monero development in under 5 minutes:
[..] I made a repository on Github and I will show you now how you can interact with it and use it to set up your own personal Monero testnet (1:34)
For more information, consult the associated Monerochan.news article4 and monero-playground4 Github repository.