What does "Sweet as" mean?
It means that is fine, no problem, or the plan works. As hangs off sweet without naming what it is as sweet as.
The saying in a sentence
The saying
Sweet as
Example
You'll pick me up at six? Sweet as.
When you use it
Use it as a casual yes when a plan or favour is sorted.
When you do not
Skip it in formal email. Write that is fine or no problem.