Paris by quarter?

Although this may not be for everyone, this is how I plan our vacations:
1) write down everything that we want to do/see
2) look at a calendars and site specific info to see if there are days where things are closed/ early close times/higher than usual traffic etc
3) Based on the time that we have in a city and the open and close times, I take things away from our list
4) I then look at planning things geographically so that we are not wasting all of our time travelling everywhere
5) pre-purchase tickets when I can and it makes sense

There may be neighbourhoods in Paris that hold no sights that you want to see, there may be neighbourhoods that have more than what can be covered comfortably in one day.

The RS guides to Paris and France include listings of the major sights that interest most tourists. You have to decide which ones interest you the most. Figure on a couple of major sights each day, probably not more than one big museum per day. Locate these on a map and group them geographically so you can spend each day in a different part of the city and not spend too long getting from place to place. If you're arriving on Friday morning and planning to visit the Louvre on Wednesday evening you seem to have more than five days -- maybe you have five full days if Thursday's your departure.

With your timeframe you may have to make some tough choices about priorities. Don't try to see and do "everything," you'll wear yourself out and your memories of the trip won't be as good. Try to tell yourself that you'll return someday, even if that seems unlikely now. Build in some time for strolling, sitting in cafes and people-watching, etc. Nobody can choose your priorities for you, and it's not the end of the world if your choices don't match others' or if some turn out to be less wonderful than you had hoped. Enjoy your trip!

My advice, don't get too locked into only seeing sights that are in the same geographical area. Yes, it's time efficient to do that. But if you can't fill the day that way, then add in something else farther out. That's the great thinking about the metro/ bus system. You're making up a guide, not a battle plan, so be flexible. Allow for spontaneity or changes on the fly.

To start, Rick has a basic itinerary in the guide book. Either adapt it to suit your needs, or just make a list of the sights/activities you'd like to see and do, then get a map and mark them out. Once you can see where the clusters are, making up your daily to do list will be easier. Don't forget to check for closed days and operating hours.

I usually have 2 lists. One is the MUST DO sites. The other is the WOULD BE NICE list that can be added in where time allows. You'll never be able to accomplish both lists on a single visit, so you'll just have to accept that (or die trying).

ETA: looks like all 3 of us were writing at the same time, suggesting more or less the same thing.

Two small museums that don't take too long and are wonderful: Musee Rodin( outdoor sculpture garden near enough to Musee d'Orsay to combine) and L'Orangerie( in the Tuilleries near the Louvre,filled with Monets' large water lily murals).

And like Sharon, I begin my planning by looking at days open/closed, times open etc.for all sites and museums.

I like to plan one major thing in the morning and one in the afternoon and sometimes one in the evening and then build around that. So we enjoy the Tuilleries as a park and might choose a picnic there on a day we want to spend the afternoon or evening at the Louvre or visit the Musee d'Orsay which is just across the river from the Tuilleries. If we plan on dinner in Montmartre, then that would be the day we take a long walk in Montmartre that afternoon and climb the tower at Sacre Couer. etc.

Less is more -- limit the number of must sees and plan on some sitting around and walking around.

Thank you all for replying. All of your suggestions were spot on for me to take into consideration like see a big museum and adding small museum and to not get overwhelmed. I want to enjoy and see the little things as well.

You can easily combine Notre Dame and Saint-Chapelle, especially if it's a sunny day.
You are not overwhelmed, you're just "over-adviced".
Booking a full day bike tour of Versailles may wipe you out.
You can easily plan to see the Louvre - but you have to get out by about 9:45 PM, when the agents "sweep" the place.
When are you going, by the way?