Q.The chenille plant
What do the tails look like when it is time to deadhead them. Just got mine a couple weeks ago, it’s beautiful. But I don’t know when to take the tails off. Mine seem to be getting a dark tinge on their outsides. I only dabble with plants occasionally. I didn’t inherit my mother’s green thumb.

You can dead head the flowers when they have turned brown or are looking quite withered.
Use a small snip to trim them from the plant and any leaves that are aging also can be trimmed from the plant.
Here is an article that will help you with care information.
https://www.gardeningknowhow.com/ornamental/flowers/chenille/growing-chenille-plants.htm