What helps you feeling better when you're feeling down?

Focusing on objective tasks, listening to music.
Anything to not obsess on the feeling and spiral. Ignore it and it will pass.
If the feeling is anxiety, then sit with it until it passes.
Don't manifest it into thoughts or words. Just let it sit in you until it settles into the general inner static.
Focus on one foot in front of the other. Count the seconds. Count the flowers. Admire your surroundings.