⦁ First of all, identify and acknowledge your ignorance as Aristotle did at the time, in this way your mind will be open to all kinds of learning. Contrary to if you live in pride.
⦁ Chess is one of the games that will help you develop your intelligence the most if you play it daily. With just two 10-minute games every day, you will stimulate your mind towards strategic thinking.
⦁ Jump rope, this is one of the best exercises that requires coordination, therefore, it will not only keep your body fit and active, but also your mind.
⦁ Practice of mindfulness that is to keep your mind always in the present and not on memories of the past or worries about the future. I assure you that it will be like resetting your mind and freeing it towards productive things.
⦁ Socialize and talk with people you meet in your day to day, even if you don't know them. For example, a girl or boy that you meet in the cafeteria, the taxi driver, the barber, the baker, etc. Social interaction with strangers stimulates your mind.
⦁ Writing also stimulates your creativity and makes you smarter.
⦁ Study and learn a new language. For this, experiments have been carried out with people over 80 years of age, who remained mentally active thanks to the fact that they were studying a new language.
⦁ Learn a new skill. There are thousands of courses on the web which can teach you how to earn money, lose weight, draw, cook, and much more.
I urge you to put these points into practice and your intelligence will increase, do not waste more time.