Cambridge Math : should I really use the question paper as my scrap paper??

Hi all,
I will sit Cambridge IGCSE Math 0580.
I've heard that they wouldn't give scrap paper, and that I should do all my trial and errors to find the answer on the question paper itself.
That seems like a terrible idea, as this phase is quite messy.
Is this true?
Thanks!

You've heard wrongly. Extra paper is always available, either at the end of the answer booklet as ruled sheets, or available as specific 'extra paper' which is securely attached to the answer booklet. However, most people find there is enough space to show the necessary working in the standard answer booklet: if you're routinely needing much more space, then you perhaps need to have a look at how you're setting out the solutions and ensuring they're modelled correctly.