1. Download 64-bit installer mit-scheme-9.2-x86-64.dmg
2. Install Scheme.
3. sudo ln -s /Applications/MIT\:GNU\ Scheme.app/Contents/Resources /usr/local/lib/mit-scheme-x86-64
4. sudo ln -s /usr/local/lib/mit-scheme-x86-64/mit-scheme /usr/local/bin/scheme
5. Type scheme on the terminal.
