Get dropped into the Paris of the Revolution, find Napoleon, tell him about modern explosives, breechloading artillery, and Minié balls: The first will be the end of wooden war ships, the second will greatly improve his strength on the battlefield, and the third will allow entirely new infantry tactics while being relatively easy to implement even with existing muskets. Also mention antiseptics, primitive antibiotics, modern steelmaking, etc etc. Get your hands on a sizeable chunk of Western Germany as a reward. Egg him on into attacking Russia, give covert aid to the Russians, and when he's on the brink of defeat, cut his supply of advanced weaponry manufactured in your territories. Use the Rhine as a natural fortification to completely smash the retreating army. Treat the retreating soldiers well: Those who lay down their arms may return home, and those who wish to do so may join you: Napoleon you denounce as a tyrant, a maniac, a traitor to the revolution and all European peoples. From your newfound position of strength against basically everyone orchestrate the quasi-unification of Europe in a federal kind of structure that will of course be under your influence.
Now re-take the colonies in North America, conquer and divide China and make them abandon their character-based writing system for an alphabet, breaking it up as a cultural entity, organise the orderly colonisation of Africa while cracking down on Belgium-style atrocities and mistreatment, and pull off gunboat diplomacy with the Japanese fifty years early, integrating them with the before-mentioned federal system.