Step 1. completely shut off or restart whatever device you are using.
Step 2. find a website where most bro mon appear for you
Step 3. open about 6 or 7 tabs of that tab
Step 4. Now wait, check those tabs often and refresh them often too!
Additional notes : if you have already caught a ton of bro mons then they become less common until the next day,
and you should not fight the bro mon until you are sure that thats all of the bro mons that have appeared.
You can also buy sweezy a coffee to make bro mons appear more often!
If you see a trash bro mon spawning in or running away immediately refresh so others could spawn instead of that