What to capture?
When you remove the colour from an image, you are left without one of the key elements that attracts the eye to an image – the differing colours in it.
However, colour is also distracting so removing colour removes a distractive element allowing the eye to focus on other elements in the image.
This image isn’t a good one to shoot in black and white as most of the interest in it is colour:
As photographer it’s your job to find other elements of interest to capture.
Look for different shapes, textures, tones and contrast in the scene that will be visually interesting and make these your subject matter.
For example, one element that works particularly well in black and white is repetition.
When you capture a series of repetitious elements such as trees, fence posts, light poles; then by removing the colour, you’ll be able to focus the viewer’s eyes on the repeated elements.