Make a list of people
Make a list of any person that you want to inherit from your will. This can be anyone you please. Also make a list of any people you might not want to give anything to.
Make a list of things
You can dispose of any property you own. If you are married, your state's laws will govern how marital property is distributed, but generally you can dispose of some portion of the marital estate. Make a list of what you own, its worth, and whether you want it to be sold and the proceeds distributed, or if you want the actual object gifted to the recipient.
Merge the two lists.
Connect the who with the what. If you are specifically disinheriting someone for a negative reason, do not put that reason in the will. Wills are public documents and can be viewed by anyone having a desire to do so.
Stop and consider
Think about how you want the end of your life to be handled. Do you want to be buried? Cremated? Donated to a scientific body farm? Your will is one of a few places you can make your wishes known. Please, I know it can be difficult to think of your life no longer existing, but the more plans made while you are alive and in control, the less stress is put on your family as they try to determine what you would have wanted.
Think about the tough questions
Do you want to be an organ donor? Do you wish to donate your body to science? Do you want a "Do Not Resuscitate" order? If you are terminally ill and in a vegetative state, what treatment would you prefer? These wishes can be consolidated in to a document called a "Living Will"
Take a deep breath
Man is mortal. Creating a will neither puts off or precipitates your eventual demise. Be smart, be proactive, plan ahead. Your family will thank you.