how can this be translated?

I have to translate the following sentence: "You had to make it all up and scare yourself daft." help! :confused:

Hi there!

Into which language/s do you have to translate it?

If it were to Spanish, it could be something like:

¿Tenías que inventarlo todo y asustarte, bobo?

Although without context it sounds a bit odd.

Hi! Thank you so much for answering me!

It has to be translated into Spanish, as you guessed.

I'll give you a bit of context so that maybe you can help me:

He wondered what other eyes had slid across these pages. He would rather have been any one of those people than himself. Their faces could be frightening, or happy.
They had come in out of the rain after doing a murder. Or they closed a book and put it down so as to go out and do a good deed. How did you know? You never did.
You had to make it all up and scare yourself daft.

This is an excerpt of a book by Alan Sillitoe.

As you can see, the sentence I need to translate (the last one) is not a question. The narrator is speaking in general about what one has to do to figure out who read

the books you are reading now. Hope this helps!

Thank you!