Answer:
Write pseudocode and create a mock-up of how the game will work and look
Step-by-step explanation:
Since in the question it is mentioned that Adam wants to develop a new game for this he made an outline with respect to game functions needed, time period, people who help him.
After that, he writes the pseudocode i.e a programming language and then develops a model i.e mock up that reflects the working of the game and its look so that he would get to know how much work is pending.