Best way to dye a dark brown carpet with a bleach stain?

http://homeguides.sfgate.com/dye-carpet-cheaply-33047.html

also will depend on the material of the carpet

Can you just use a brown permanent marker. Since it's permanent the color should stay in the material. If you clean your carpets and it gets lighter with cleaning--then you can just retouch it.

you'll likely have a better chance of matching the color with paint (windsor newton makes good acrylics) because the dyes in an acrylic carpet are added while the fiber is being made, and not even the expensive Procion dyes will take.

There used to be a fabric dye by "Rit" which came in all sorts of colors. Find the one that matches and follow the directions on the package.

You could try using some Rit Dye, they have 2 formulas - one for natural fabrics and one for synthetics.... they have a color chart on how to mix a color..... I've seen many DIYers use a spray bottle to apply the dye, the water must be hot..... https://www.ritdye.com/instructions/spot-dyeing/