what to do if not enough information on requirement code example

Example: not enough information on requirement

So what to do as a Tester is I had
to depend on my judgement in this case.
I din’t need very detailed requirements
to start testing, so I start by thinking
about high level scenarios that test the
concept of the story, rather than waiting
to get full clarification about the featur
e and losing time. By drafting high level
test scenarios, even when the details change,
the context should still be the same.
When test cases are written on the basis
of high-level use cases, changes in feature
details will result in minor variations
in test scripts. This is because the context
and the wider user journey remains the same.
So instead of waiting for PO to give me full 
description and losing time, I start working
on creating tests.