The following is an Amal for a person who is continuously troubled with nightmares:
Write out this Naqsh in the state of Wudhu facing the Qiblah whilst reciting Durood shareef and make into a Taweez.
Make 4 Taweezes like this. Tie one Taweez to each leg of the bed.
If a person is sleeping on the floor then place one Taweez in each corner of the pillowcase.
InshaAllah one will find relief.