Here's a more comfortable way if you want use the cd commands to certain directories more often. It avoids writing the directory name every time.
In your .bashrc or .profile, insert:
# activate cdable_vars
shopt -s cdable_vars
# define shortcut for your directory, here DIR
export DIR="/Users/<username>/path/to/your/dir"
Execute your script once: . .bashrc
Then you can cd to your directory like this:
cd DIR
This should work even if the path contains spaces.
In shell scripting, however, you must quote the variable like this:
cd "$DIR"