The beginning guard against tyranny was Federalism, which is a political concept in which a group of members are bound together by covenant. James Madison had stated in a “Federalist Newspaper” about Federalism and how it basically worked for the Colony. Federalism protects against tyranny because Federalism isn't an absolute power, its a division of power to certain members of a covenant.
The additional guard against tyranny was Separation of Powers which means the government was separated into different branches. The Constitution states that the Separation of powers were legislative, executive and judicial branches. Separation of power can defend against tyranny simply because there is 3 powers, not one; which does not make America have an absolute power.
The third guard against tyranny were Checks and Balances, which were the balances in the 3 branches of power. In the constitution, there is a diagram stating which branch has power for each other. This power protects against an absolute power because if each power checks on each other, they are certain that they will not become powerful then one another.
The last guard against tyranny was the Big States versus the Little States which means that each state will have certain amounts of senator’s ( The bigger the state, the more senators). Articles in the Constitution state that a certain amount of representatives will be chosen for the amount of a states population.