بسم الله الرحمن الرحيم
(Fatwa: 560/560=M/1430)
For good memory, recite ya Qawi (یا قوی) after every salah resting the hands at head. Also, pray to Allah for the same and avoid things leading to forgetfulness.
Allah knows Best!
Darul Ifta,
Darul Uloom Deoband
