What can one do to increase his memory and focus?
Here are a couple of brief tips:
1. Guard your gaze and your ears. There can be nothing more distracting than television, a wrong glance, or a tune that won’t go away.
2. Recite after every salat the masnun du’as. In addition, recite “Ya Qawiyy” eleven times after every salat, or recite this du’a seven times: “Allahumma Nawwir Qalbi bi ‘ilmika wasta’mil badani bi ta’atika
اللهم نور قلبي بعلمك واستعمل بدني بطاعتك
Recite this same du’a seven times before opening up a book to read or study as well.
Also, you can recite “Sanuqri’uka fala tansa” سنقرأك فلا تنسى three times after every salat.
3. When you sit down to study, minimize any nearby distractions. Also, in order to maximize your usage of time, keep a book unrelated to what you are studying nearby and whenever you tire of studying, distract yourself with a book on another subject to refresh the mind. Sometimes it is good to get up and stretch.
4. Memorizing is easiest when done with someone else. Memorizing alone can be difficult and takes much longer. Having someone quiz you can cut memorization time to at least one third.