Inf. Please do not worry. Bill: The rain is going to soak all our clothes. Tom: Not to worry, I put them all in plastic bags.Sue: I think we're about to run out of money. Bill: Not to worry. I have some more travelers checks.
There is nothing to worry about; there is no need to be concerned: "But not to worry: it all ... falls into place in the book's second half, where the language is plainer"(Hallowell Bowser).