Usually a smooth operator is someone who tends to be "on top of things", and in is usually in control of any given situation.
If he/she isn't in control of a situation, they usually find a way to gain control of it to make it more awesome for everyone involved.
Smooth Operators are rarely in trouble, and, when they are, they can usually get out of these situations quickly, elegantly and with a zero percent chance of casualties.
Julie thinks "That Kevin is one smooth operator."
Everyone agrees, and life is awesome.
2. They may also be cunning, wily, and might be willing to lie, cheat, or steal to get what they want.
You can refer to the song "Smooth Operator" by Sade, read the lyrics, and it may help you.
It has good and bad connotation, it all depends on how it's used.
2. That man is a smooth operator, he just dumped a girl and has a date with two new ones.