Blonde still too orange

I used to get my hair highlighted @ a salon - foil highlights on my natural blonde hair.  As I get older it gets darker   I think the stylist said it's a 7 (1-10 I guess) in the Matrix (not sure) blonde shades.

Anyway, I quit my job for health reasons last yr and can only go to the salon a few times per yr instead of every 6-8 wks for foils   I attempted at-home highlights again - I don't know why, b/c I always goof up, but I was desperate.  I am trying to come up with some $ to get into the salon but think I might be stuck for a while.

I used a few highlighting kits, including Clairol Frost & Top, Clairol hairpainting, and L'Oreal Styliste.  I left the highlights on 15 min, 15 min, then a half hour but some areas are still orange. 

Should I try one more time to get the orange areas blonde?  I don't want to look like I poured bleach on my head.  If the areas are still orange after 15, 15, then 30 minutes should I try one more time @ a longer amt of time?  Like 45 min???

Each time I think I got rid of the orange I end up catching myself in a mirror with some orange spots.  Aaaaaarggghhhh!!!

Also, what about adding in lowlights?  I saw a kit at Walgreens - I think it was L'Oreal but am not sure.

 

PPS Get the highlights right before you start thinking about lowlights...

I have the same problem Im a natural 7 too. If you do go over the highlights use 10vol peroxide. Bleach over bleach can = breakage. Check it often if you have to do it a few times. Its better to use 10 vol and have to repeat it then uto use 20-40 and have it break off. Next time Id just use bleach with 20 vol and just keep checking it. With 20 vol I can get to a very pale blonde it I leave it on long enough. Heat speeds up bleach too :)