The Great tit has been building her nest for some time now. The male bird does little to help so she can decorate exactly to her own taste. Typical nesting materials are grasses, moss, animal hair and small feathers. As far as the location is concerned she prefers some kind of cavity, in an old tree, a nesting box or even a wall. She has been furnishing her nest with quite a lot of moss already, I bet this will be a comfortable nest!