Best hair dye that doesn't look flat or wrong?

[Justchillaxing]

I've dark brown hair, below shoulder length and very curly. For a couple of years I've been using nice n easy dark brown to cover the few white roots that were coming through. I had my hair cut last week and have now realised there's more grey/ white than I thought and want to do something about it.

Am I better using semi permanent or permanent? What brand is easy to use and looks least fake? Can I get away with a brown with copper tones or am I kidding myself that it'll look ok? I really can't afford to get it done at the hairdressers but don't want to make a mess of it, hence preferring semi permanent.

Any advice?

Thanks. I think I'll try it with one and hope for the best. It's not very long, medium thick.

I've bought the dye! I chose l'oreal casting creme in auburn henna .. hope it's not too bright!