How do I use this German word?

AP German student here. I consider myself to be good at German, certainly much better than my classmates, but I can't figure out how to use "sich ausdenken".
I don't understand how it fits together.

My best guess is "Ich habe es mir ausgedacht," but I am not sure whether that's correct. I appreciate any help.

Yes, that's correct.

Native German here.

>>1
what does it mean. Also I'm think of making an irc chan for learning languages. What do you think?

That's Correct.

Another native German.

Yeah that would be cool

Oh that does mean, "I invented that" , I hope thats correct my english isn't that perfect.