I will be in Berlin for 4,5 days. How can I best maximize my time there?

I will be staying in Berlin for 4,5 days. I know what the major sites are, but I was wondering if anyone could give me some suggestions for an itinerary so that I could maximize my time in Berlin(as I don't have a clue how much time is typically spent at each place). Do you have any general safety tips for Berlin (I am a 22yr old male and will be traveling alone)? And my last question, do you know any special deals that allow you entry into all of the major tourist sites for a fixed price?

A lot depends on how much money you have to spend and what your own particular interests are. I'd divide the time in three. One day for general sightseeing, one day to visit selected museums - you can't do them all - there's nearly 100 of them, one day for Frederick the Great's palace of Sanssouci in Potsdam. That leaves a day for any special interests.
Begin with one of the four hour walking tours, or bike tour. That will give you an introduction to the historic sights (with exceptions such as the Olympic Stadium , the German/Russian museum where the surrender was signed and the STASI museum, the museum about the secret police of the GDR and the allied museum about the British/Americans/French in Berlin. Museums not to be missed - Pergamon, Altes, Altes National Gallerei all on museum Island. If you have the time - the Culture forum (bus 200). Sanssouci speaks for itself. Safety tips - don't get too drunk. All the usual things in any big city around the world. Berlin is by world standards very safe. Night life - Kreuzberg - Oraienstra脽e/Heinrichplatz (bus M29) Public transport - excellent. A two hour oneway ticket transferable to all modes of transport (except taxis of course) costs 2.10鈧?an all day ticket 5.80鈧?@ these apply to zones A and B (You'll easily understand when you look at a transport map) Good deals - Berlin Welcome Card from the tourist information offices. Buy a good guide book before you go, there's loads, Lonely planet, Fodor, Timeout and this one http://www.berlin-explored.com

You need to have some book about Berlin and just look over it and marked with marker what you want to see there. Berlin is a big big city and historical so much things to see so you can make some plan where you want to go. But 4,5 is enough to see important things.
Brandenburger Tor, ZOO, Strasse 17. Juni, Kurfuerstandamm, the new big train station, just opened last year it is huge, Check Point Charlie, many museums, galleries, parks... there is so much. Have fun.