You can be the light in someone's darkness in many ways.
Here are just a few examples of how you can be someone's light:
1. Providing a listening ear to someone who needs to vent or talk
2. Providing resources, phone numbers, and vital information that can be helpful with the situation the other person is facing. An example of this is providing suicide hotlines, therapy phone numbers, and information that shows how depression can be treated for someone facing suicide thoughts or depression.
3. Do a fun activity you both would enjoy, like going out to the movies or for lunch.
4. Leave an instant message, email or voicemail (It helps to say that you don't expect for them to get back to you but you wanted them to know you were thinking of them, that way they don't feel obligated or pressured to reply if they don't feel up to it.
5. Go out for a walk together or exercise together
6. Share inspirational quotes, videos, songs, and/or movies