Questions to ask:
What scenario are you preparing for?
Why are you leaving your home/office/city/area?
Where will you go?
When will you be returning home?
Who will be coming with you?
How will you be traveling?

I kind of broke my packing list down by groups. If you're evacuating to a family or friend's place your needs will be different than if you're going to a hotel/motel in a different town, or if you're evacuating to a community shelter.

Look at the items that you need or rely on daily, i.e. medications & hygiene items. These are things that you'll need to have available wherever you are. Depending on the event, you may be able to pick them up at a local store.

My categories are:
First Aid
Administration (papers, contacts, etc)

I also added a list of things to grab on the way out and where they were.

Depending on how much time you have to evacuate will depend on what you are able to grab. As we saw in the fires in California recently, there was a knock on the door and you were told to leave immediately.