The adjective expression ALL THUMBS means extremely awkward or clumsy:
I’m all thumbs when it comes to origami.
He’s all thumbs with repairing stuff.
I’d love to help you, but I’m sort of all thumbs today.
I took some guitar lessons, but I was all thumbs with that so I gave up.
When it comes to talking to girls, I’m all thumbs.
Here’s the video version of the article: