Warmth is a choice
A warm-toned image can feel quiet and cohesive, particularly when colour would compete with the subject. Start by looking at the light and the midtones. Decide whether a subtle warmth supports the picture or simply repeats a familiar visual effect.
Let the material remain visible
Paper, fabric, wood and skin each have their own texture. Strong toning can flatten those differences if it is applied without care. Check the brightest and darkest areas, and leave enough separation for the photograph to retain its shape.
Think about the final print
A screen preview is only one way to judge a finish. Paper colour and surface also influence how an image feels in your hand. Try a small print before committing to a larger set, and compare it in the place where it will be viewed.