Coibius said:
I'm assuming you're not just straight telling them that for safety reasons. Are you programing the energy at the end of the affirmation to let the cursed know it came from you?
Hagl and Thaur is good for cursing but you should be really focused when handling those energies. And yes do tweak the affirmation to let them know it was you, for sone people who are open or whatever, they will find out it was you automatically if you dont remove your trace or if you dont detach the curse from yourself, i found this out by experience.
In order for them to also be afraid of you and never think of abusing or harming you ever again you might also wanna add Fehu and change the affirmation a little bit.
Something like: " X is now ( whatever you wanna do to them ). X is aware that this curse has come from me and avoids me and avoids harming me in every manner, in positive ways for me."