Technically, this is not a difficult process. And it is not illegal to browse the Dark Web. You simply need to install and use Tor. Go to
www.torproject.org and download the Tor Browser Bundle, which contains all the required tools. Run the downloaded file, choose an extraction location, then open the folder and click Start Tor Browser. That's it.
The Vidalia Control Panel will automatically handle the randomised network setup and, when Tor is ready, the browser will open; just close it again to disconnect from the network.
Depending on what you intend to do on the Dark Web, I recommend placing tape over your laptop's webcam to prevent prying eyes watching you. A tinfoil hat is also an option. be careful