Hmm, orbital bombardment would definitely announce our great return to the galaxy, though I am afraid we'd come off as another Empire of Sith jerks. How would it make us different from the other Sith Empire? The Jedi will immediately crush us. My idea is not to get officially involved in 'evil' actions, rather do some good deeds and claim we are the good reformed Sith, clearly separating ourselves from the other Sith factions. We could outlaw slavery, for example. This will give our enemies one less reason to attack us.
In order not to lose working power, we will make unemployment a crime. Totalitarian regimes have plenty of work for everyone, so if we get all citizens to work for the good of the Empire, we will not lose any working power by outlawing slavery. This will also lead to our citizens having food and a place to live, mostly eliminating the possible problem with starving and homeless citizens. Sooo, we will look good in the eyes of the public.
And last, we should give proper education to everyone. Building a generation that fully believes in our ideals and lives to serve the Empire. Leading young people into being patriots willing to join the army. Give them the most basic military training few years before they are old enough to sign up for the military or navy, which will make it seem natural for them. We could even extend our offer to poor orphans outside of our space. The Jedi and the Republic do not care about them, but we won't let that potential manpower for stormtrooper corps go to waste, will we?