Basic maintenance = bleach virgin hair before the roots get "ugly" (personal preference I personally like to let mine grow a bit). sometimes I have to bleach twice. then tone all over (wella t-18 or t-14 for me)
I've actually been experimenting with a bleach bath and I basically add shampoo to my bleach and developer and just rub it on my head like shampoo until everything is covered followed by a rinse and normal toner process. I know I'm not supposed to bleach the roots AND the already bleached hair, but the bath was faster. I mean way faster. But I do think overlapping causes some breakage, so I'll only do that again if I really need a quick hair fix.
Bonus: My light hair is fantastic for chalking. Totally late to the chalking game, but I can have purple hair for one day and blue the next so it's swell.