Everyone's favourite word and yet no one really knows what it means.
So let's break it down:
Toning is the process of losing body fat while building muscle.
The processes:
Building muscle; Anabolic Process (gain)
Losing body fat; Catabolic Process (lose)
These processes are the exact opposite of each other so it is possible but it really isn't recommended.
While it is possible to build muscle and drop body fat at the same time, it is really not advised, it's kind of like working a minimum wage job and buying a Lamborghini, yes you'll look cool when you're driving it but let's be honest you are going to hate your life when all you can afford to do is sit in it and look at a wall as you can only afford to drive 5 miles a week all while not being able to go out and socialise etc.
So toning for a regular gym-goer is going to be terrible, you'll probably have to say "no" to every friend that asks you to go out for food and say goodbye to nights out.
It is much more realistic to go on a cut for 6-12 weeks depending on what your initial body fat percentage is. 250-500 calorie deficit, slightly increase your cardio and boom you will be a lean, mean, tasty machine.
If you are completely new to exercise this will already happen it's something called "Newbie Gains" as the stimulus to the body that has been otherwise sedentary accelerates muscles growth this will happen in the first year then it will start to slow down.