I'd imagine you'd have to use an ascii image generator and give it an image to ascii-fy within certain dimensions.

But as you can see, I haven't changed my profile picture either so idk what the best way to go about it is.

ykw, you just gave me a great idea. I am gonna see if I can make an ascii image generator that accepts some image you give it, and throws out an ascii version of it within whatever dimension char accepts. I don't know how long it'll take for me to finish the app but I'll begin work on it tonight!