I'm a runner and I train in the morning several hours before dawn, about 4:30am. It is completely quiet in my neighborhood. The air is still and everyone is still sleeping. It is the most quiet and peaceful part of my days. The only noises are my footsteps and breathing, and my running partner's panting and nails clicking.
I had a few thoughts in my head, but I found that creating the word map was a very helpful reference while sketching/brainstorming.