trick
The Italian word 'trucco' is used to describe a trick, a cunning or skillful act or scheme intended to deceive or outwit someone. It can also refer to a trick in the sense of a clever or skillful action, as in 'pulling a trick'. In a broader sense, it can be used to describe a method or technique, often a simple one, that is used to solve a problem or accomplish a task.
Your makeup is very beautiful.
In this sentence, 'trucco' refers to cosmetics or makeup. This is a common usage of the term, where it is referring to the makeup applied on one's face, which enhances or alters the appearance.
The trick of the trade lies in experience.
In this context, 'trucco' translates to 'trick' and is being used to imply a special or efficient way of doing something. 'Mestiere' translates to 'trade', hence 'trucco del mestiere' refers to a trick of the trade, which is a clever or unusual way of performing a task in a particular field.
Without makeup, she looks like a different person.
Here, 'trucco' is used again to refer to makeup, emphasizing on the transformational quality of cosmetics. The sentence points out how someone can markedly change their appearance just by not applying makeup.