My natural hair colour is dark brown and the number of gray hairs appears to be multiplying by the day - I would guess I am maybe 15-20% gray (hard to judge).  The contrast between the dark brown, make the gray look even worse.

I am currently dyeing my hair with a dark brown permanent.

I want to go to a mid-brown or a mid golden brown.  What is the best way to do this?

Should I use colour remover and then put the new dye in?  Also on the back of the boxes of all mid browns it does not have dark brown (as a before/after colour option) - does this mean I cannot use mid brown on my hair?  I thought permanents could lighten up to two shades?

Help appreciated as I am so confused!

If you want your whole hair to be lighter, I'd suggest using a color remover like Colorfix to get rid of old dye, then apply another dye or toner afterwards to get a lighter brown shade. Go for a neutral base one, so that you don't end up with a funky green ashy color :P

Another option would be to do some foils with bleach, a little highlights will make the hair appear lighter, and add dimension.

good luck.