In this example, circles represent the states of the environment and arrows are state transitions. There is only a single action choice from every state except the start state, which is in the upper left and marked with an incoming arrow. All rewards are zero except where marked. Since the choice of optimality model and parameters matters so much, it is important to choose it carefully in any application. A system with a hard deadline would be appropriately modeled this way.
All unlabeled arrows produce a reward of zero.