Etiquette

When dropping off a meal, plan not to stay more than 10-15 minutes. This will obviously depend on your existing relationship, but it is safer to expect that the meal recipient is not ready to entertain yet.
Arrive at the requested time.
Make enough for leftovers. Freezable meals are also nice.
Don’t forget the extras like drinks, condiments, salad dressing, and dessert!
If there are children in the household, consider including a special toy or treat for them to help with what may be a transitional time.
If you plan to have something delivered (e.g. pizza), make sure to pay for a tip in advance and specify the delivery time.
If possible, deliver your meal in a recyclable or reusable container.
Be sure to label any items that you would like returned to you. Include a large paper bag that the recipient can use to store your items until you can coordinate a pick-up date in the future with the recipient.
Include clear preparation instructions, i.e. "Bake for 1 hour at 350 degrees."
Consider including a note or a card to the recipient wishing them well.
Have a map to the recipient’s house and a phone number in the event that something comes up on the day of delivery