Getting texture files that are stored separately

I've purchased a few Blender files from CGTRADER and most of them are great, but I just got one that stores its texture files in a subdirectory.  Naturally, the object appears as a grey lump.  As I am still new to Blender, I cannot figure out how to link those separate texture files to the .blend object.  Can anyone please give me EXACT instructions (I'm a real newbie) on how to tell Blender where to find the texture files it needs to properly display the object?  Thanks!