There are many practices that can increase intelligence, including using online time for educational purposes, reflecting on learning experiences, spending time with intelligent people and explaining new concepts to others. Intelligence is hardly a fixed quantity, and changing personal habits can help increase brain power.
One easy strategy to get smarter is simply to be more deliberate with time spent online. The Internet is filled with educational resources, including free college courses, vocabulary training, informative essays, TED Talks and educational podcasts.
Instead of dedicating work or school breaks to social networking or blogs, consider browsing an educational site instead. Keeping a learning journal that serves as a record of each day's learning can also help improve intellect. It doesn't have to be especially articulate or elaborate, but a brief recounting of new facts or skills can help better commit new learning to memory.
Although it can be humbling, spending time around other intelligent people is a highly useful way to raise intelligence. Spending time with brainy people can increase exposure to new ideas and modes of thinking as well as present challenging conversations that can improve intellect.
In a similar vein, one of the best ways to retain new learning is by explaining that learning to someone else. Try to explain new concepts to others in order to make sure they're fully understood and recalled.