The glitch allows the player to obtain a Pokémon from another Pokémon's nickname, such as "D" (hex:83) resulting in Mewtwo and × (times sign) resulting in 94, as long as the character in the Pokémon's name is not a control character, unlike other CoolTrainer♀ corruption glitches which depend on sub-tiles from a map.
As CoolTrainer♀ corruption can fail due to its random name containing a hex:50 character after viewing it on the Fight screen, it is suggested to scroll on the menu until it works. If it doesn't work one action to get it to work may be the increase or decrease the number of bytes in memory that are hex:50.
1) A seven letter long player name.
2) A Pokémon with a certain nickname. The second character will determine what you get (see old man trick) e.g. DD will give Mewtwo. Note that you'll get glitch Pokémon instead of Trainers.
3) Pokémon with the CoolTrainer move in the first position. To get this with Ditto, battle a Pokémon with more than one move, transform and then switch the position of a move after slot 1 with move 1, and end the battle.
4) A Full Heal.
1) Go to this position then open and close the items menu.
2) Enter a battle then do a CoolTrainer. Though the glitch may work outside of a cave without a freeze, it also may not so it may be a good idea to go in Diglett's Cave before entering the battle to avoid the freeze (but you should not open the start menu again after opening it in the correct spot).
3) Switch to the Pokémon with the relevant nickname. You'll notice that the Pokémon's nickname has been printed on the screen near its sprite.
4) Heal Ditto with a Full Heal (this updates the screen copy too), then switch to it.
5) Do a CoolTrainer with Ditto again. Don't open the items menu or view the Pokémon screen after it's sent out or you'll mess up the glitch unless your Ditto has a nickname you want.
6) Catch the Pokémon to get a Pokémon based on the nickname.
You can also do this with the Ditto itself if it's nicknamed. Do this glitch as usual but open your items menu when Ditto is sent out again (for the second CoolTrainer).