What are the historical first steps to imposing autocracy? Is there a pattern?

The way this question is phrased it looks more like a request for a recipe to follow, like in the "steps to take". But this is of course very hard to generalise. Turning this on its feet again is the part of "is there a pattern?"

Is this more about becoming a tyrant, that is increasingly doing tyrannical things, being a tyrant? Is this more about becoming a tyrant, rising into a position the enables one person to do tyrannical things, being a potential tyrant?

Ignoring the oxymoronic framing of time arising from the juxtaposition of "throughout history" and "free press", there seems to be a very simple pattern, identified as early as Plato and Aristotle wrote about ethics and politics.

Hence the road to power in Greek commercial cities was simple: to attack the aristocracy, defend the poor, and come to an understanding with the middle classes. Arrived at power, the dictator abolished debts, or confiscated large estates, taxed the rich to finance public works, or otherwise redistributed the overconcentrated wealth; and while attaching the masses to himself through such measures, he secured the support of the business community by promoting trade with state coinage and commercial treaties, and by raising the social prestige of the bourgeoisie. Forced to depend upon popularity instead of hereditary power, the dictatorships for the most part kept out of war, supported religion, maintained order, promoted morality, favored the higher status of women, encouraged the arts, and lavished revenues upon the beautification of their cities. And they did all these things, in many cases, while preserving the forms and procedures of popular government, so that even under despotism the people learned the ways of liberty.
(Referenceing Aristotle, Politics, 1310a by Will Durant: "The Life of Greece" Simon & Schuster: New York, 1939 pp. 122–123.")

The main pattern to observe is:

1. An economy produces too much inequality and discontent, whether most of the time real or sometimes just imagined (usually this is thought to appear in a severe downturn, but it is just as likely in a recovery period or even a statistically flourishing economy; these statistics do not cover the distribution or feelings about it)
2. Then a charismatic champion emerges that unifies the support of the lower and middle classes against the current leadership.
3. If the current leadership resists its own overthrow with violence, the equally violent response to this gives the charismatic rebel his means to attempt to seize power. That includes both volunteers and a general wish of "restoring order".

4. Once in power former supporters need and receive, at least initially, something to show for their effort and support, some promises have to be kept (in brackets are examples of how a well known modern tyrant might compare to this):

   • real share of wealth (Hitler raised employment)

   • imagined share of community (Hitler defined a Volksgemeinschaft, "us against them", conveniently also serving the wealth goal above, for some)

   • imagined share in political decisions (Hitler claimed to represent the Volkswillen, a Rousseau-like general will

These are of very basic patterns, but they might be traced in Cromwell, Robespierre, Lenin, Mao or even in less negatively viewed characters like George Washington as well.

It is therefore distracting to just look at the oppressive things a tyrant does. If they are not directed at the direct enemies the future tyrant sees as obstacles in his path to power, they are negligible. Oppression measures develop slowly, over time, when the tyrant is already in power. Note that in the modern tyrant example case the ground work for oppression and censorship was handed over to his control just like the office itself. When the modern tyrant attempted a coup in 1923 by sheer force, it failed, quickly, because of the key missing ingredient: popular support.

Further reading:
Randall Collins: "Weber and the Sociology of Revolution" (2001)