A very good memory is necessary to remember useless and unnecessary information and therefore, this memory is loaded with piles of useless garbage. It's much more appropriate and much easier to remember what you like, and therefore interesting. Try to learn what you like.
Interest in the subject is supported through the finding of new and original conclusions about it. Stagnant, ignorant, and formulaic minds are not able to generate new conclusions, and therefore can not focus attention for a long time.
When you get rid of strong pleasures, tastes and other emotions, you have a decrease in the threshold of sensitivity and your sensitivity increases. You begin to distinguish small details. You become attentive. Mindfulness is love. Mindfulness will allow you to see beauty, and beauty will give you joy and energy.
Forgetting is the same as destroying in the real world. Thoughts are forgotten, things are destroyed. In order not to forget, you need to build well, slowly, carefully and constantly repair. In order not to be destroyed, you need to repeat constantly, maintain attention and take your time, doing everything slowly and carefully.
Thinking and remembering should be approached in the same way as building in the real world. Forgetting is destruction. You need to build slowly and carefully, constantly using what you have built, updating and repairing it.
Forgetting is the process of running away from contradiction. Unable to resolve the contradiction, the brain prefers to forget about it. To improve memory, you should cultivate humility and integrity of the paradox, which consists of two contradictory parts of information.
I do not advise you to abuse memory training, the better a person's memory, the more he is an idiot. Why would he? He remembers everything by heart. However, bad memory is also not a sign of a big mind.