Using Quick Mask

Open your image, click on Quick Mask and with Black as the Foreground Colour,

use the Brush          (or Pencil) Tool

to 'paint' over the parts you need to be either masked or selected.  In practice it doesn't really matter which way around you begin as when shown as a 'selection' the area can be swiftly  'Inverted by Select > Inverse (Ctrl+Shift+I).

The example I've chosen is to select the spectacle frames on these large sunglasses, then once selected, alter the colour by changing the hue. Using the traditional selection tools this would be a tedious job but Quick Mask makes it easy!