Unclear question. However, I answered from a general writing perspective.
Explanation:
Remember, a notice is a piece of writing usually done with the objective of letting others become clearly aware of something or to do something important.
So, as a guide your notice could read;
LOST ITEM
"A blue-colored watch has gone missing yesterday within the school premises. Please if found bring it to the office of the school management. Thanks".
Answer:
*insert picture here*
