Experiment with different lighting. Adjust the proximity of a lamp; how do the shadows change? Which objects are highlighted, and which are hidden? How would the piece look with the lamp as part of the still life?
A still life is simply a collection of items, typically against a plain backdrop. Fruit is a reliable example, but you could try books, old electronic hardware, or busts. For painters, it might take days to get these onto canvas. For photographers, it takes minutes.