Learn to see warm and cool colors. This is a skill best perfected by looking at objects outdoors and comparing 'color chips'. Squint to simplify (see photo/graphic of simplified tree color chips from the video in the Download tab). Seeing color shift of warm/cool is hard to do from photos and easier in person. Set up a white object outdoors on a sunny day to start seeing colors. Look at white buildings. Then ease into warm/cool color for objects (trees, road, rocks, etc.).
Practice! Once you start seeing warm and cool colors you can continue to learn! Go easy on yourself in the beginning, sometimes it takes a while. There will be a moment when you 'get it' - after this you must still practice the visual concept to hone your skill. Often students will say they think they get it only to have it slip away, keep practicing... this is when you know you are close to keeping this special way of seeing for good. You are un-learning what your brain is telling you (but it's only a white cup, there is no color). With practice you will see more and more color in shadows and light.