My attempt to edit the color of an item ended in disaster

[Spir Aabye]

Forgive me if this should be basic knowledge, but I am returning to the game after not playing for years and forgot some things about editing.

I attempted to darken one section of an item, and the whole thing turned one solid color. Trying to fix it, I could only change the color of the whole item, not the individual part of it. So I feel kind of silly asking this, but I spent way too much time attempting to figure it out on my own, but how do I select a specific part of an item without selecting the whole thing when I edit it?

[Hintswen Guardian]

At the top of the build window you should see an option for "edit linked" thats what lets you edit a single prim in an object.

Select that then click the prim you want to edit.

[Trinity Yazimoto]

if your linked object had no solid color before but just a texture (even multiple one), turn the color to full while and normally it should be back to the original. then do what is said above... select the linked parts and change the color on the parts you want.

[Drongle McMahon]

You can also select individual faces of a single (linked) object, with "select face". However, if the object is a sculpty, it only has one face (strange hacks apart).