Dictatorships can be very difficult to achieve and maintain, but that doesn’t mean it’s impossible! You’re going to need a near unquenchable thirst for power, an awfully self-centered attitude, and a charismatic smile. Start working on building charisma and the ability to detach yourself from your subjects. You can do this by taking a smaller leadership position to practice caring less about those below you and charming everyone into liking you better. It will be brilliant practice.
Then, you must choose a country to take over. I would avoid countries such as the US, Canada, and highly civilized European countries. These places have a highly educated population and bothersome ‘check and balances’ to keep things in place. A good idea would be to topple an existing dictatorship. This can either be done by overthrowing an unpopular dictatorship, or inheriting power when another dictator dies.
You must be in a high position of power to inherit the dictatorship, and you must be careful because others will want that position as well. However, if you are not in a position to inherit a dictatorship, you may take over an existing one. Overthrow a dictatorship that is unpopular and oppressive, and generally the public will be on your side. Other countries to target are economically unstable, weak governments, and countries undergoing famine. Build a support and take over your chosen country.
So, now you’ve got a country. To efficiently control it, you are going to need a scapegoat. This is a minority group or foreign government that you blame all your problems on. Is John over there a threat to your power? Accuse him of being a member of your scapegoat and lock him up!
Scapegoats should never be a majority in your country, they’ll overthrow you. Rebel groups, foreign governments, or political or religious groups are a fantastic way to start so you can turn away all the hate meant for you unto them. Bad economy? Only because of the sanctions X country imposes on us! And JOHN is a spy for X country! You can begin passing specific laws against the scapegoat, and sap away rights as you do.
“All people accused of being a spy for X country get no fair trial,” but write it in fancier, harder to understand words and call it something like the “Safe Citizens Act.” Now you can lock people up for no reason just by saying you think they might be from X country!
Now, you’re really going to want some strong public support. Build a tiny base of core supporters, who can advise them. TRUST NO ONE. If your supporter group gets a taste of power, they may want more. Be careful not to lay too much power into the hands of anyone, especially your core supporters.
Then, build a wide, general public support base. To keep public opinion on your side, provide your subjects their basic needs and give them a few minor freedoms. Just don’t give them all these freedoms at once, they might get hungry for more.
You can study dictators of the past or read pieces like 1984 or Animal Farm for inspiration and borrow some good restrictive policies from them. Careful, though, don’t get too ambitious and do NOT try to conquer Russia in the winter. This was the downfall of both Hitler and Napoleon.
Send out a lot of pro-you propaganda, especially in schools and other public places. Try to be friendly to outside nations (unless they are your scapegoat or an ally of your scapegoat) and try and make your country more economically secure. This will help sway the world to your side in the coming days as you eliminate all opposition to your near limitless power.