My natural hair is dirty blonde, but I am constantly dying it and changing colors. The color that reappears the most, and my current hair color, is platinum blonde. Maintaining platinum blonde hair is hard and tricky work. When I get my roots done and dye my hair, I get highlights all over instead of bleaching my whole head. This is still harsh on your hair, but it is much safer than straight bleach. After that is done, I pay an extra $10 for a cellophane toner. This goes on purple and cancels out any yellow, gold or brassy colors in your hair, leaving it with an icy, white and silvery appearance. This also makes your hair very moisturized and soft to the touch. Without this, the dye would cause my hair to be very dry. I would love to hear how all of the other blondies out there keep their hair looking good.
I came on here to mention using purple toners, but clearly you've got that covered! From what I can see in your photo your hair is a lovely colour and looks in nice condition. I went through a phase about 5 years ago where I dyed my hair blonde, firstly as a base to get bright colours on top, and then to just be blonde. I was never able to shake off the gingery notes in my hair and it drove me insane. Even now when I dye my hair brown it goes sort of red. I use purple toners even for my brunette hair and it's worked wonders at lessening the harsh coppery undertones. I hope somebody comes along soon with more tips for blonde hair for you!
Yes, the purple toners are great! I have also had the same problem with dying my hair brown and having it turn red and coppery, I wasn't aware that the purple would work for that too! Thank you!