New Highlights

A: It's puzzling that your new stylist is having difficulty achieving even color results with foil highlights, especially since the foil method typically offers more precision and control than cap highlighting. One of the main advantages of using foils is that they allow the colorist to isolate specific sections of hair with much greater accuracy, making it easier to place highlights exactly where they're needed and to maintain consistency during touch-up appointments.
Since you mention that your hair is in excellent condition, you're actually in a great position to make a fresh start. Going back to a uniform dark brown base color is definitely possible and would give you a clean slate to work with. This process involves using a darker dye to even out all the different tones in your hair and create one consistent foundation color.
Once you've achieved that uniform dark brown base, you'll need to wait at least two to four weeks before adding new highlights. This waiting period allows your hair to recover from the chemical processing and ensures that the new base color has fully settled. When you do move forward with new highlights, you'll have the opportunity to work with your hairdresser to create a highlighting pattern that's easier to maintain and touch up consistently.
I'd also suggest being more involved in the consultation process with any new stylist. Don't hesitate to ask detailed questions about their highlighting technique, how they plan to maintain consistency between appointments, and whether they keep detailed records of their work. A professional stylist should be able to explain their process clearly and should welcome your questions rather than dismissing them.
Remember that while your hair is currently in good condition, any chemical processing will have some impact, so it's important to maintain a good hair care routine throughout this transition. Using deep conditioning treatments and minimizing heat styling will help ensure the best possible results from your color correction and future highlighting services.
©Hairfinder.com
See also:
How to color hair
Highlighting with foils
Highlighting with a cap