Budh Navagraha is the deity associated with intelligence and
memory in Hinduism. Below is a mantra to improve intelligence and memory. It is
dedicated to Budh Grah. The mantra should be chanted 108 times daily in the
morning just before sunrise.
The mantra is:
॥ ॐ बुं
बुधाय बुद्धिमते नमः
॥
The mala used for chanting the mantra should be made of Tulsi Beads and it should contain 108 beads.
Along with chanting the mantra one should waking early morning and drink a glass of water in which Tulsi leaves was put in the previous night.
Read Bhagavad Gita daily - at least 7 shlokas daily - is highly meritorious as it provides more insight into various aspects of life.