Pravana Violet Photo & Bleach Advice Request

Hi all, I've been dying my hair violet for years. In this photo, it's a combination of months of special effects deep purple, and probably the last 4 recent months have been Pravana Violet. (The under layer is black)

My friend on the right, had Pravana done at a salon, but it didnt take well, so he went over it with a Manic Panic.

I'm trying to cut back costs though and am looking for bleach help.

I usually purchase boxed bleach kits from a drugstore or walmart,target, with the powder, developer pre-measured and in a small amount. I eyeball half and use it for my roots. save the (unmixed!) leftovers, and use the other half for next root bleaching. All done by guessing half. No measuring.

I really think I should finally buy bleach powder and developer myself though, to save money. But I can't find clear mixing directions online.

I planned to buy from http://www.discountbeautycenter.com/

(because it's the best place I can find for

http://www.discountbeautycenter.com/43127-pravana-chromasilk-vivids-color-protecting-sealing-spray-33-oz )

Can anyone recommend what you use to bleach your hair & how much? Or does it come with directions? I've sometimes gone to a hairdressers home for dye help, and I've looked at the powder bucket & developer bottle and didnt see clear mixing/measuring directions. She just knows as a hair dresser.... I've googled a bit, but again, no clear directions and I assume different brands have different amounts needed..

I don't want to buy supplies for a hair dresser, and have it turn out that they didnt come with instructions, because it is assume that you know already.

Does anyone mind clearly posting what you use, and how much you mix?

From what i know I need bleach powder, liquid developer. (I've read to use 30 or 40 for your roots, yes?) that's it.

I also can order from saloncentric.com, sallys, or amazon if you can link those. Thanks!

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