In what order do I do this?

OK, Your roots are your natural colour, is that correct? If so there is no point in using a colourstripper on them it's just not the product you need!

When you talk about stripping the colour and doing the roots are you talking about stripping the colour from your lengths as well or were you just referring to the previous question - you don't need to use a colour stripper at all if you are just doing your roots and refreshing the colour on your lengths (unless you are changing the colour!).

You may get a stripe, it depends on a lot of factors! You need to keep the bleach warm (but not applying heat) and covered and keep an eye on how it is developing.

How catastrophic overlapping is depends on how bleached and how damaged your lengths are, if they are super light or damaged I would be very careful as they could begin to break, but if they are not too light or damaged I would say be careful but you would probably be ok if little bits overlapped here and there (still better avoided but probable won't do too much harm) of course this will then lighten those bits further and make it less even, plus it can turn any dye you have on those parts into an unwanted shade (the red I used to use went neon yellow if bleached!).

Are you doing a full bleach or a bleach bath? What is your natural colour?

What purple did you use last time and what purple are you using this time?

Yes, my roots is my natural brown-grey colour. But I thought I needed to colorstrip or something to get the new colour to stick to the hair in the lengths even though I'm using the same color, which was Special effects Pimpin Purple. I'm planning on doing a full bleach on the roots, because the result was nice.

What is a bleach bath?

What is a bleach bath?

Sorry! Reading up on it now!

Sorry, only just saw this! No you don't need to do anything to the lengths before applying the same colour again, just lighten the roots!