weaving blond

I have dark brown hair with lots of gray. I've been tinting my hair, auburn, for years. Now days I have so many gray roots that I retouch every two weeks. So I want light ash blond streaks. I did my hair medium brown with L'Oreal Preference. Then I used L'Oreal Highlighting kit that lifts 5 levels. I used a cap. The results are good except the streaks are strawberry blondish. How do I get them to be light ash blond. Better to go with my olive skin and to blend with the gray roots. Should I use a toner (what is that) or next time use a light tint. (will tint bring it up blond enough) Thanks, Jan