(put something) in a nutshell adverb phrase
In a nutshell, what I want to say is that you should make changes to your lifestyle to be healthier.
I want you to tell us about this plan in a nutshell.
Stop beat around the bush, you just tell the story in a nutshell.
Anything that could be written in so few words that it would fit into a nutshell would have to be brief and to the point (Picture source: vectorstock.com)
The first text that was supposed to be enclosed in a nutshell was far from small. Pliny the Elder recorded an event, which he apparently believed to be genuine, in Natural History, the original of which was written in AD 77 and was translated into English in 1601 by Philemon Holland, who included explanatory notes, like this:
We find in Histories almost incredible examples of sharpness of the eyes. Cicero hath recorded, that the poem of Homer called the Iliad, including 700 pages of A4 text and being written on parchment, was enclosed within a nutshell. The same writer maketh mention of one who could see to the distance of 135 Miles.
To keep optimistic or have hope that something positive will occur and simultaneously prepare for a negative outcome
All I can do is hoping for the best and preparing for the worst.