How to decrypt WingDing?

Since there is NO section for tutorials or anything a like for Undertale for some reason (I can't explain!), I decided to post it as a skin. I know it's wrong, I know it shouldn't be done, but I truly wanted to share this amazing page with you! Enjoy decrypting the hidden WingDing messages in Undertale.

Site: http://grompe.org.ru/static/wingdings_gaster.html

Note: I did NOT make this site, neither do I take credit for it. I am simply sharing it.

(Download contains a poorly edited picture).