1. WRITE A LIST - make a list of all the things that have to be done before you leave, along with a list of all the things you need to pack for your trip. This tip is helpful in reminding you of what you need. At the last minute your mind is so clustered with things it would be easy to forget something important like your passport if needed.
2. PACK ONLY WHAT YOU NEED - when packing think about where you're going and what the weather would be like so you pack the right clothes. Also pack items that are versatile and can be worn with other items in your closet, this will help eliminate packing too much stuff.
3. TAKE A PICTURE OF YOUR LUGGAGE - This is helpful if you have more than one luggage for your trip. When being dropped off at the airport looking at the photo will help remind you of all items that need to be unloaded. This is also helpful if, God forbid, you have lost or delayed luggage.
4. TAG LUGGAGE - I either tie a bright ribbon or colorful paper tag on the handle of my luggage so I can identify which luggage is mine when on the carousel. When so many other luggage look alike this helps you to pick out your luggage easier.
I hope this helps, happy travel!