بسم الله الرحمن الرحيم
I started reciting Soorah Mulk when Ummi told me that my grandfather and my uncle both of whom have passed away (May Allaah have mercy upon them) recited every night after magrib. Alhamdulillaah they have memorised the soorah too. I pray that it intercedes for them and that they are protected from the torment of the grave.
One day I started copy writing Soorah Mulk. This way I could easily memorise the whole soorah in few days because I was reciting it every day. Alhamdulillaah.You can also try! You can memorise it by reciting it daily.
'Abdullaah ibn Mas'ood said: "Whoever reads 'al-Mulk' every night, Allaah will protect him from the torment of the grave. At the time of the Messenger of Allaah (salallaahu 'alaihiwasallam), we used to call it al-mani'ah (that which protects). In the Book of Allah, there is a chapter [and] whoever recites it every night has done very well." [Sahih at-Targhib wat-Tarhib, no. 1475]
This Hadith means that on the Day of Resurrection this Surah will intercede with Allaah for the forgiveness of its reciter. (Commentary from Riyad-us-Saliheen)