Completely messed up my hair color.. Need advice!

So my hair started out as dark brown. I decided I wanted to gradually lighten my hair at home. I removed most of the color using the vitamin c method and got it to a light/medium gingery brown. I waited a month and used a high lift blonde by ion. It turned out a dark blonde but quite orange so I waited a month and did it again. This time things went bad. Most of it got to a medium blonde with some warmth, but the top layer of my hair about 4 inches from the roots went pale yellow. And there were pale yellow splotches throughout the rest of my hair. I used a purple shampoo to tone it immediately after dying so the pale yellow parts came out completely white, and the rest a medium ash blonde. It looked ridiculous, like I had a white stripe in the middle of my hair.

But I waited a couple weeks. I didnt want to lighten it anymore because it was in terrible condition so I decided to try and match the white parts to the rest of my hair. I bought a medium ash blonde, knowing it might go slightly green tinted but was hopeful. Luckily I did a strand test, and yes, it went green, so I didn't use it. Then in my ridiculous mind I thought, maybe it would look better if I used the purple shampoo to make my hair even more ashy and the white parts a pastel purple.

Because the purple shampoo also has some blue tones mixed in with it, and I may have left it on too long, my hair actually looked more blue than purple. I washed my hair twice this morning and it came out mostly. But I am now left with hair that has a million different tones. about 5 inches of my roots are still a medium ashy blonde. My top layer is a murky blueish purple, and the bottom layer went a greyish blue, with a hint of green. It's probably not as bad as it sounds, the tones are very faint. It just looks off. And I know after a few more washes my hair will be back to white and warm medium blonde.

I just don't know what to do after that. I cant go to a salon, for money reasons and I just don't want to. Every experience I've had has been terrible and needed to be corrected anyway. I would like to go to a dark ash blonde. What I was thinking I may need to do to fix this is:

1. Let the blue/purple tones fade back to white.
2. Use a warm medium blonde just in the white parts to stop it turning green in the next step.
3. Use a dark ash blonde on all of my hair. Hopefully this will cancel out the warmth in my roots and the warmth from the dye in the second step, without it turning green.

If anyone thinks this will work or has some better advice please let me know! Sorry this is so long but I'm desperate