I have been in Europe for the past week and while here, I have noticed that subtlety equals sensuality when it comes to hair color and cuts. With a few exceptions, when the hair color is overpowering it distracts from the person themselves.
When I see stark color change or dramatic color, most of the time it's not flattering. You should stay within a range of your natural color. If you are a dark blonde it is okay to do light blonde highlights. If you are medium brown, do gold highlights etc. They are complimentary tones, they accent your own natural color and they add vitality to your overall look. You wouldn't do red highlights on a blonde; therefore, don't do blonde on a redhead. The same goes for blonde highlights on a brunette.
There is a reason why clients ask for consultations - they are seeking your professional advice. The client may have an idea of what they are looking for, but they don't really know what will look best on them. It is our role to give our clients direction (i.e. "Here is the shade that would suit you best.")
What I notice on the street is that what stands out are the mistakes. When you see beautiful hair you don't think of it as beautiful hair because of the color or cut". You just notice it as beautiful because it is done right. It is complimentary to the person. Bad hair color, bad hair cuts, they stand out - they are not complimentary of the person and their personality, which looks unnatural in their appearance.
The objective is to accentuate the natural beauty of the person and not to over power it with color or sculpting haircuts that are not complimentary.
When you give a consultation you are giving advice. It's not just listening and doing - it is discussing with the client what the options are. That is the definition of professionalism.