I need help in AppleScript with TextEdit

I need to create an AppleScript that creates a new TextEdit file, write text, give it two options to choose the font, then the same with the color, save the file on the desktop and close TextEdit.
This is what I have so far, but I came to an extreme of my knowledge:

Tell the application "TextEdit"

Make new document with properties {text: "XDXDXD"}
set the desktop path to the path of the desktop folder as text
say the front document
set font to "Comic Sans MS"
set size at 40
set its color to {65535, 0, 0}
tell him at the end

tell him at the end

I'm not sure how to say what does not work from the previous script. Can you help us complete the script?