How do you activate mystery gift on Pokemon pearl?

Answer 1

first you have to beat johan and josep!!! they are really hard!!! how to VS them is to finish the sinnoh then go to proffeser rowan talk to him and oak will come then he will give you national pokedex then go to enterna then talk after go to julbilif and win a lottery then save then go to battle tower and enter single battle and you will VS josep in the sixth round and johan in the seventh and if you win they will activated!! THAT IS THE EASIEST WAY !!!! THIS IS NOT A LIE!!!

Answer 2

first you go to jubilife city tv centre and talk to the guy on the third floor. he will ask you to give him a quote tell him wifi everyone or something like that. he will then give you mystery gift. save it turn off your game then turn it back on. you will see mystery gift at the part where you select your game to begin the game.