From Daily Writing Tips:
1. “All hands on deck,” from the traditional nautical command for every sailor to report for duty, refers to the necessity of everyone involved to lend a hand, or assist.
2. To bite the hand that feeds you is to be hostile to someone who has been kind to you.
3. To be a dab hand is, in British English, to be an expert.
4. “The devil makes work for idle hands” is a proverb that means that inactive people are susceptible to the temptation to do wrong.
5. To know something firsthand is to be directly familiar with the facts.
6. To force someone’s hand is to compel them to act prematurely or involuntarily.
7. Having a free hand is being given wide latitude about how to carry out a task or responsibility.
8. To gain the upper hand is to obtain control.
9. To get your hands dirty is to engage in a important activity that may not be pleasant.
10. To give a hand is to help, though it also refers to applauding by clapping one’s hands.
Link to the rest at Daily Writing Tips