I usually teach this as a corny family tree, with Government being the father of 3 sons, and each type of government has a personality based on their characteristics.
Auto-selfish and controlling
Oli- clique' and a snob
Dem-friends with everyone
I then go into how each son, had 2 children, and do the same with monarch, theocracy etc.
The thing I didn't add to the chart is the hybrid gov of Monarch & Parliamentary Democracy: Constitutional Monarchy (Great Britian & Japan)
This usually helps students categorize and organize the types of Gov. in their minds.