Take a High Dynamic Range picture every day for a week
Take a picture of a different flower every day
Take a Macro picture everyday, using the macro mode of your camera, a macro lense, reverse ring, or whatever other option in your hands.
Take a picture in the "Golden hour" daily for a week
Describe the country you live with pictures
Take pictures of any subject making their color the most important thing of the picture
Take a Black and White picture every day for a week
Describe your day with a photography, you don't need to be the subject of the photo!
Take a picture of a different animal everyday
Post everyday one picture of something that you have seen, or happened to you today.
Take a picture of a different insect everyday for a Week