The White Balance filter works well by following these steps:
Restore “Neutral color” and “Color temperature” to their defaults (6500 degrees).
Click on the eyedropper and position the crosshairs over an object which is supposed to be white, e.g. a white card, white shirt, etc. and click.
Thanks Dan. I was just looking for more information on the White Balance tool and incorporating it into my workflow.
Just looking for a clarification, though. I’m coming from the photography world where we try to use 18% gray as a target for the White Balance eyedropper. In fact, card stocks are made with this color for that very purpose. Is it different in the world of video editing? If I click on something that is absolute white (I’m guessing, something that is close to #ffffff), theoretically I could click on a section with blown highlights and not get an accurate white balance. Those blown highlights would be #ffffff no matter what the overall white balance is for the rest of the image. Again, I don’t know if this is similar or different from the world of photography.
Of course, you can use a better methodology such as a 18% gray card but the advice above is for the majority of users who have not shot something like that. You can certainly apply ideas and best practices from photography to video as well.
Thanks! I didn’t want to break the program. 
You don’t really need 18% gray. 18% gray is for exposure per Kodak and Ansel Adams. You can use any white subject as long as it doesn’t blow out for white balance.
White paper is not so good, because it contains optical brighteners, which distort the result. Better suited is a natural paper, without brighteners. This looks somewhat grayish. White porcelain is also very suitable. But possibly wise it is too bright.
If you have a gray card or something similar, at hand, you should already do the white balance in the camera.
Surprisingly, the eyedropper also works quite well, even if there are no neutral objects in the image, if you capture the whole image. And if this automatic changes the colors too much or too little, then you can readjust very excellently with the slider: “Color temperature”: Warmer or colder, depending on how you want the image.
Question: What do you apply first:
White Balance or the correction of brightness and contrast with Levels (or Color Grading)?
Both work, but which is the better way?
I suspect Wihte Balane.
I’m afraid if you stretch the tonal values to the limit with Levels, Wihte Balance could become a problem after that, because it spreads the tonal values again, so it could lead to clipping.
Or
Gratitude fills my heart for the incredible effectiveness of the White Balance filter! With a simple restoration to default settings and a click of the eyedropper over a white object, the magic unfolds. Thank you for simplifying the path to perfect color balance – a true game-changer! 
Apply white balance first, then adjust brightness and contrast with levels. Stretching tonal values with levels before white balance could lead to color clipping issues.