It means you have a talent or skill for something.
A knack is a talent for something. Here are some sentences.He's got a real knack for painting.I wish I had the knack of gardening.Constructing furniture takes a knack.
To have a knack for/of something means to be particularly good at it e.g. "He has a knack for scoring important goals" See Richard Lester's film 'The Knack...And How To Get It' - one of the male leads is successful with women (he has 'the knack'), while the other male lead is nervy around women (he needs to get 'the knack' so he is more confident around women)
KNACK
The skill, knack, feel; aim
The Knack was created in 1978.
The Knack ended in 2010.
Nack is not a word, however in British and US English "Knack" is a word (pronounced with a silent k) , which means to have a skill or tendency to do something. For example. "John had a knack of cheering anyone up."
Knack is a noun.
The duration of The Knack ...and How to Get It is 1.42 hours.
Knack Productions was created in 1967.
The Knack ...and How to Get It was created on 1965-06-03.
Get The Knack was created on 1979-06-11.