Okay, I know almost no one who likes thinking about their own mortality, but for the love of pete (and your executor/loved ones) take the time and make plans now, while you are healthy and of sound mind. You don't need anything complicated (especially if you don't have a lot of assets).
I'm not a lawyer and I don't even play one on TV, but based on watching other people go through this in my lifetime, her are some basic ideas to allow your grieving loved ones to grieve your loss without adding to their stress.
This is a time to remember that you may be the sole point of contact for several networks of friends, family, loved ones, professionals, government entities, and organizations. You are the only only person who makes this network work, once you are gone, a bewildered person is going to have to take up the reins of your life at least long enough to bring it gently to a halt and not have everything come crashing down around them.
1. Make a will. Regardless who draws it up make sure that it is clear and to the point and that you understand what you are legally asking your executor to do. Have an executor and an backup executor and make sure that they know about each other and consent to doing this for you. If you have children or pets make sure that your will is clear about who will be their guardians in your place. Get consent from those people before writing them into your will.
Your executor and backup should know where your Will and other important paper work is kept. If you change your organizational system, then tell them (or better show them so they can picture it if they need to).
Do not put your will in a safe deposit box at a bank-- if your executor is not a signer on the account they will not be able to access it in a timely manner (much like "open box with enclosed crowbar").
2. Keep the following with your Will (and update it yearly-- most of this could go in a binder):
- any power of attorney/advance medical directives
- how you want your remains disposed of (including details if you have a specific donation program arranged)
- a list of insurance polices, if any (you may have a bunch of incidental polices through credit unions, work, or even credit cards-- they may not pay out, but if you signed up for them keep a list)
- a copy/printout of your address book (if you are feeling particularly generous you could annotate it with clues for your executor as to how you know people)
- a list of the banks and credit companies that you have accounts with
- a list that describes where the title deeds to things like cars mobile homes RV's, or other assets are kept
- a copy of your safe deposit box key (or a note where to find it and which bank it is at)
- a list of major assets and identifying information (car, IRA's, house, pensions, etc.)
- a list of personal property that you want to go to specific people (most wills have a clause that refers to such a document).
- a list of agencies you regularly interact with & account numbers (Social Security, Medicare, any federal, state, local, or community organizations that either support you or that you support)
- a list of your recurring monthly/quarterly/annual bills with account numbers and contact info (house payment, utility bills, property tax)
- a list of your email, and social media accounts
Side note: If you have very specific body donation requests, that all needs to be arranged in advance with the program you hope to donate to. If they need proof a particular diagnosis for your body to be useful in their study-- lining that up now and making sure the person with your medical power of attorney knows the details will make it much more likely you can benefit science in the way you want.
Even if you are an organ donor, it is good to make sure that the loved ones/family who would likely be charge at your death know your wishes. Giving people time to get used to the idea makes it more likely your intentions will be honored-- especially given that there is a very short time window after death for plans to be confirmed and carried out.
The upside to all of this is that if you go through the steps of getting organized all you have to do is update it once a year and cull old/outdated information and if you have some other type of crisis (that doesn't result in you dying) you will be able to quickly lay your hands on important documents in an emergency.
Quick test: If you own a car, can you find the title in under 5 minutes?
Now imagine your stressed out loved one trying to find it in amongst all of your other things.
Organize your paperwork and document your wishes and then put it aside and live your life.