Since I haven’t seen a list around of DMR-related events, here are the ones I could find.

All those events happen on BrandMeister, I’ve never used any other DMR networks.

World-Wide Check-In

Happens every Saturday at 16:00 UTC in talkgroup 91 (World-Wide).

The world will be called region by region, and all you have to do is say your callsign in phonetics alphabet only when your turn comes.

Simple as that. Please avoid barging in without listening, this can delay the net and isn’t good radio etiquette. In any case, if you missed your country or region, there’s always a call for missed and late check-ins for the region and world.

They also have a search function to see if your call was registered correctly. The logging is also done from multiple master servers, so not a lot should be missed.

FinDMR Check-In

Happens every Sunday at 19:00 (Europe/Helsinki time) on talkgroup 244 (Finland).

One word of warning: this one is mainly aimed at hams licensed in Finland, or Finnish-speaking hams. Basically, English-speaking OH- callsigns will be called first, then all of Finland from OH9 to OH0. At the end, another call for English-speaking OH- hams is done, as well as late and missed check-ins. Lastly, the last call is for Finnish hams residing in other countries.

FinDMR also has a page where you can see the results of the check-in live.

Aussie Check-In

I must admit, I didn’t know about that one until very recently. I was listening to TG91 (worldwide) on Thursday when I heard VK2AFK make an announcement for a quick net going on TG50520 for Australian callsigns and anybody who would want to join.
Turns out there is a net every Monday at 08:30 UTC on TG50520.

This one seems to have less participants than the two other mentioned, so do show up if you can! More participants are always better!