It's not easy to get smarter, and there are very few things you can do that might make you smarter that have any kind of scientific evidence to support them. (However, you really should exercise more. There's plenty of evidence that points to exercise having benefits to your brain and your intelligence.) If you really want to get smarter, though, check out a few of these links before you attempt anything.
If you'd like to read more awesome and interesting stuff, check out this unrelated (but not entirely random!) Techdirt post