If you use a professional white balance filter, you can manually white balance the image in the camera itself. However, when you have a busy day with shooting, you may not have enough time to white balancing in camera. This is why you should handle white balancing during the editing process. In order to get the perfect white balancing, you will have to start it from a neutral point; you can start with middle gray.
When you use Adobe Lightroom, you can start it by utilizing the eyedropper tool that is located towards the white balance sliders. In this case, you will have to search for the pixels that are almost 50% in the RGB section. To save some time, you should try determining the darkest blacks that meet the whites (if it is possible). After identifying such area, you should select the respective pixels to get a neutral white balance.
Now, you can manipulate this image to be a warmer or a cooler one depending on your requirement. Then, the tint levels must be set according to the desired values.