How do you dye fabric successfully?

[stirling]

Hi
In actual fact it's an armchair cover. The material is very tough - a bit like what sacks are made from. The cover of my armchair is removable, but care instructions say dry clean only.
I'm now wondering if I can dye it at all. It's a really stunning chair, to be rehoused in my sons room rather than binned. But it's a faded green colour, clashing with his room. Ideally should be grey.

Any tips please?
Thanks

What fabric is it made of? I’m not sure from your description if it will dye. Cotton works really well, man made fabric doesn’t. The other options you’ve got are to get it reupholstered (expensive) or throw a throw over it (Cheap).

Thanks FaithInfinity, looks like jute or canvas...

First thing would be to wash it I think. If it is intended to be dry cleaned it may shrink a little though.
Is the fabric content not on the care label?
PP is right - home dyes such as Dylon are effective on cotton, viscose and linen as they are natural fabrics but don't take well on polyester and nylon.
Link to Dylon Smoke Grey - www.dylon.co.uk/en/home/products/machine-dye/grey-and-black.html

Thanks rosegoldwatcher, about to check your link...