As the name implies, dictator is another "abuse of power game," such as "Asshole."
Begin play by have all players draw a card. The player with the highest card is the dictator. The dictator then announces some card-based condition(s) and deals out as many cards as he likes (try to keep it less than 5 per player). For every card a player has that meets the announced conditions, they take a drink. The dictator is also dealt a hand of cards, except giving, rather than taking drinks. After dealing, the dictatorship passes to the left.
Easy conditions are: all odd cards, all red cards, etc (as always, be creative). Conditions can be combined. For example: if the conditions are all red cards drink once, all even cards drink once, and all aces drink twice, then a player with the ace of hearts would drink four times (face cards are Jack=11, Queen=12, King=13, and Ace=14).
Variation: The dictator can use other non-card based conditions as they want. This is the reason and rationale of being dictator, to change the rules as you please and keep the game interesting.