Read a new book at least once a week. This is one of the easiest way to work out your brain because you are pumping your brain with new ideas and vocabulary. However, do not read too much such as several books in a day. Try to read books on subjects that would be useful in life such as physical health, financial wealth, and social relationship.
Hang around winners. By hanging out winners they’ll influence you to be winners too and there will be stimulating conversation instead of boring you to death. If you’re currently hanging out with losers, get away from them immediately. Try to make friends with some winners.
Try new things everyday. Maybe talk to a new person, try a new sport, try a new exercise, etc. Whatever it is, try something new every single day as it will expose you to the world and you won’t become so bored.
Be conscious/aware of things. Do not just do things or live your life unconsciously. Instead, learn to be aware of your environment, people’s body language, and implications made by people. This is very crucial to being intelligent and it’s what separates humans from animals.
Change your routines or habits. If you go to work everyday the same route, it’s time to change it. If you do the same morning ritual, change it. If you do the same exercise everyday, change it. If you eat the same food everyday, change it. You should only do something once a week unless you’re trying to master a skill. Doing something too much will bore you to death and you won’t improve. Also, your intelligence will decrease by doing something over and over again.