While photography offers an easily accessible practice that facilitates a focus on the world around us; sketching can take this further as we focus on a specific subject and create something representing it.

Take a notebook (or tablet, which I think works better as it allows you to easily correct mistakes, draw on different layers though does sacrifice some precision). Find something interesting to sketch. Of course artistic techniques and ideas are useful (draw one part first and do other parts in proportion, think about negative space, perhaps do a quick line drawing and then add a layer of colour).