Use the "cd" command at the terminal to navigate from one directory to another. For example, you could enter "cd nibbleguru" to navigate to the "nibbleguru" directory inside the current directory.

"cd /" to go to the "/" directory
"cd ~" to go to your home directory
"cd .." to go to the parent directory

You can combine these as well, like:

"cd ~/nibbleguru" to go to the "nibbleguru" directory inside your home directory
"cd ~/../" to go to the directory that is the parent of your home directory
"cd /usr/local/bin" to go to the "/usr/local/bin" directory.