First of all, totalitarian states are characterized by a single authoritarian ruler, who concentrates all the state powers on himself. Moreover, a big propaganda mechanism surrounds him to make his person attractive to the citizens in the country. Many times, even a personality cult has been developed towards the leader.
Other main characteristic is the lack of individual freedoms in such a state. It is the goverment the one who prevents the citizens from enjoying them, as this is form of exercising control over their behaviours. By banning certain attitudes, an authoritarian ruler aims to erradicate any possible opposition or the spread of ideas by detractors who could convince others in turn and challenge his power.
For example, freedom of speech is restricted, together with the freedom of association. There is mass control of the media as well, mass surveillance and intense political repression. This later creates an atmosphere of general fear that prevents citizens from breaking the rules.