First, check https://meshmap.net/ to see if anyone is around. If not, you can be the first (it just will be very quiet).
Next look for a device. I’m partial to this one: https://www.seeedstudio.com/SenseCAP-Card-Tracker-T1000-E-for-Meshtastic-p-5913.html - just make sure whatever you get it’s spec’ed for your region.
Then just download the Meshtastic app on your Android or iOS device and you’re set.
Sam Altman will be watching this case with interest. Maybe he can get a new round of funding from this guy.