Positives work better than negatives

When we're aiming for accuracy or certainty, we often think it's clearer to use negatives.
 

Notice will not be effective unless it is delivered in person or by courier.

Don’t forget to submit your dietary requirements before the meeting. I don't want to be dealing with complaints on the day.
 

What a buzz kill

These things suddenly feel hard to do. And you come off as – to put it nicely – someone who could be having a better day.
 

People respond better to positives

This notice must be delivered in person or by courier.

Last call – let me know your dietary requirements before the meeting. I want to cater to your needs!

To teach myself this skill I banned myself from writing no, non, and not for 3 months. It worked! It's amazing the workarounds you can come up with when you give yourself a hard line.
 

A mantra that helped me

Tell them what they CAN do, not what they can't do.