Try this
- Ask whether now is a good time for a short account, then describe the specific thing completed.
- Say what kind of acknowledgment you would enjoy if you know. Avoid making an elaborate celebration the only acceptable response.
A worked example
“I finished the task I kept postponing. Could I tell you about it?”
An invented example to adapt, not a real exchange or a script you have to follow.
Before you leave it here
Let the response be natural; a quiet acknowledgment can still be a real response.