一手

a skill / mastery of a trade / by oneself / without outside help

one / single / a (article) / as soon as / entire; whole; all; throughout / "one" radical in Chinese characters (Kangxi radical 1) / also pr. [yao1] for greater clarity when spelling out numbers digit by digit

hand / (formal) to hold / person engaged in certain types of work / person skilled in certain types of work / personal(ly) / convenient / classifier for skill / CL:雙|双[shuang1],隻|只[zhi1]

to show off one's abilities / to exhibit one's skills

first-hand

to hold back a trick / not to divulge all one's trade secrets

to take care of a matter all by oneself / to run the whole show

to have a skill / to have a lot on the ball / to have an affair

lit. one hand exchanges the cash, the other the goods (idiom) / fig. to pay for what you want in cash / simple and direct transaction

lit. to hide the sky with one hand / to hide the truth from the masses