It totally depends on what you're lighting up. There are lighting pages that you MUST consult before doing this. It's literally an art form. I just went through it for a complete home renovation (hundreds of lights) and there are distances and wattage and colors for accent lights, art lights, task lighting, etc. Lighting is super important and there is too much for me to go through in my answer here ---you need to go to the Houzz lighting pages and find the part that discusses your specific application and go from there.