it depends on the game mode
That won't work too well. Because people have no idea what to expect, they will be minimally prepared.
The least you could do is make a list of gamemodes that might appear on the server.
Also, this is just an aside, but you've misspelled "match" five times.
Just as well, your server isn't actually online. Are you sure your server actually functions?
Also important is that you haven't set a time for this tournament to begin at. You can't just start a tournament out of nowhere and expect full attendance.