1) Get rid of the distractions

You can't multitask.

To put it bluntly, research shows that we can’t multitask. We are biologically incapable of processing attention-rich inputs simultaneously.

All those buzzing text messages and email chimes can reduce mental ability by an average of 10 IQ points. For men, it’s about three times the effect of smoking marijuana.

2) Get your sleep

If you’ve missed sleep, you’ve reduced your intelligence.

Via Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School:

Take an A student used to scoring in the top 10 percent of virtually anything she does. One study showed that if she gets just under seven hours of sleep on weekdays, and about 40 minutes more on weekends, she will begin to score in the bottom 9 percent of non-sleep-deprived individuals.

Think you’re just fine cheating yourself on sleep? Of course you do. But you’re wrong.

5) Believe in yourself

Want to be smarter? The first step is to believe that you can become smarter:

Those students who learned about IQ’s malleability improved their grades more than did students who did not receive this message, and also saw academics as more important than did students in the control group.

Surround yourself with people who believe in you and you’ll perform better:

Via The Heart of Social Psychology: A Backstage View of a Passionate Science:

…Rosenthal and Lenore Jacobson (1968) did the same study in a classroom, telling elementary school teachers that they had certain students in their class who were “academic spurters.” In fact, these students were selected at random. Absolutely nothing else was done by the researchers to single out these children. Yet by the end of the school year, 30 percent of the the children arbitrarily named as spurters had gained an average of 22 IQ points, and almost all had gained at least 10 IQ points.