At the end of the battle screen where your EXP value is visible. Again there are some steps needed BEFORE you can cheat your EXP.
I wish I could make it easier for all of you but games creating code on the fly requires to "trigger the creation" of the code used by the trainer.
Sadly more and more games are built using such an environment, nearly +80% of indie titles. Therefore reading the trainer notes became a necessary step and if you have any questions left feel free to ask.