You're Not Crazy: Holiday Checklist

This page is a continual work-in progress. I don't expect that this is exhaustive, but feel free to add your additions to the comments, and I'll them to the master list. These are in no particular order.

There are a lot of halachic issues below. I suggest spending some time learning the halachot of yom tov. I found Laws of Yom Tov by Rabbi Simcha Bunim Cohen to be very user-friendly, but it presumes at least an intermediate-level understanding of the laws of Shabbat (and, like all English halacha books, is stringent in its interpretations).

Remember that you can transfer fire, but not create new fire. The best way to have an open flame in order to light yom tov candles on the second day of yontif is to use a yartzheit or Catholic candle. In many stores, you will find these large white candles in a glass jar with saint candles. It will just look like a "blank" Saint candle. Avoiding avodah zara is a good idea. You can find a picture of a "blank" candle here. Remember not to extinguish it! (Or place it next to a window or fan!) Also don't place the candle directly below the fire alarm. Think about how you would handle the situation if your fire alarm went off on chag.

Figure out your meal situation. Will you be eating at home or someone else's home? Plan your menus. Have snacks available for between meals.

Figure out your davening situation. If necessary, reserve your seats at the shul of your choice. If you can't afford seats, speak to the rabbi or office as soon as you can.

Grocery shopping. Much cooking can be done on the yontif, but that is beyond our conversation.

Do any necessary (or desired) cleaning.

Figure out whether/how you will bathe during the yom tov. This is especially important if you have young children.

Let the people who matter know when you are unavailable. Tell them at least a week in advance, and then remind them again. Maybe you also want to change your voicemail message and/or email auto-reply.

Pay any bills that will come due during the chag.

Write out all service times, even if you aren't sure you want to go to something.

Check your timers, lights, and alarm clocks. Put your phone on the charger so that it's not dead once the three day chag is over. This is especially important if your phone is your alarm clock!

Run the garbage disposal so that it doesn't get stinky over the next few days. Same with the dishwasher.

Make sure you have enough clean clothes and underwear. This is important; don't forget it.

Set up your eruv tavshilin, if the chag will extend directly into Shabbat.

Implement your cooking plan. Prepare your stove/oven, if needed. If you have a non-yontif-friendly stove/oven, plug in your Shabbos plata or set up a blech.

General:
List of Jewish Holidays with Hebrew Dates
Months of the Hebrew Calendar
Chodesh tov! What's Rosh Chodesh?
The Disasters Known as My First Three Day Holidays
Can Women Shave During the Omer?