Okay the real deal:
Palpatine is Sidious. Palpatine realized that jumping into the limelight as the new HEAD OF THE SITH, would be a useless trial in which he would certainly lose to the power of the Jedi. Sidious is not all-powerful, but he is mighty! As Palpatine, a senator for Naboo, he realized that by manipulating certain factions, he could place himself in a position to be elected chancellor. That was the entire premise behing TPM. He knew the in's and out's of his home world and so he jeapordized his people so that he might get elected. Playing the Trade Federation for fools and strong-arming them as Sidious was the perfect ploy. Meanwhile, as Palpatine, he slowly slithered his way up the ladder, and manipulated everyone in his path, included Queen Amidala.
Advance to the end of TPM. The Queen's reign is almost over (as mentioned in AOTC, it is only for 2 terms), and she will now be needing to pursue other avenues of politics. In the meantime, she, most probably on the suggestion of Palpatine, opts to appoint Jar Jar as a senator. Palpatine knew that after the mass destruction the droid army caused on Naboo, both the Gungans and the Naboo people would have to form a new pact, alliancing themselves to grow into a democracy or at least a proper symbiotic cohabitation. The Queen, selected Jar Jar to go to Coruscant, a perfect place for Palpatine to watch over him and "guide" him. In AOTC, when Padme was heading back to Naboo, Jar Jar was requested to act in the best interest of Naboo. Notice how slyly Palpatine suggests someone with much gumption request that the chancellor be given full executive power through an emergency act (Not unlike the US's FEMA deal with the President). Now, as Sidious he has control of the Trade Federation, and the newly formed separatists, headed by his new apprentice Dooku. At the other end, he has full control of the Republic and "permission" to create an army.
Ten years prior he knew that the attack on Naboo had stirred up many complaints that the Republic really didn't have the capabilities to handle interplantary disputes on the scale that the Trade Federation had initiated with their droid army. As wiley as he is, I am certain, he put into motion through the other Jedi master (can't remember his name) to start a secret army of clones (genetically programmable, easily manipulated - i.e. not fully sentient - able to make decisions, read free will). By instigating more trouble with the droid army and the separatists, eh would be able to "magically" come to the rescue of the galaxy with this "secret, but now revealed in the nick of time" army. No one will care that this happened, because 1) he just got permission to build one and 2) he just saved the galaxy from "terrorists" as it were. Becauset he clones are more efficient, he cuts his ties with the droid army, destroys the separatists, his alter-ego: Sidious, remains secret, and it looks like a renegade Jedi master, once the Paduan of Yoda, is behind it all. As Palpatine he is a hero and he slowly pushes his budding army throughout the galaxy where he will soon be able to, in one fell swoop, take full control. Remember in ANH, the Emperor dissolves the senate, giving control to regional governors who have a surplus of storm troopers (next level clones) at their service.
All this done without really revealing he was a dark lord guru force master.
So, in a nutshell: Palpatine=Sidious and as both identities, he put into motion this entire plan in order to gain power on both sides, manipulating both sides, taking down both sides...and eventually controlling a galaxy. Albeit for only a short while...4-6 years.