Approaching tutorial creation can be a daunting task. To make things easier, you'll need to formulate a plan. If you have a content lifespan document or a player progression flow at hand (both mentioned in Chapter 3, Scoping a Game Project), use them as a basis. Otherwise, make a basic timeline of the player's progression and a separate list of important game mechanics.
Now, try to match both lists and note the teaching techniques you could use. Ensure that you do not overwhelm the player with too many unrelated concepts at once. At this stage, you may find out that parts of the game or its level design need to be changed or swapped around to make things fit better. This is a big part of the reason why the beginning areas ...