I use the EasyVFR app (works on Android, IOS and Windows - details from Google I'm sure) for my flight planning - if you want it will produce a briefing sheet of all NOTAMs relevant to your route (and allow you to filter out ones on the route but not relvant to what you are actually doing), shows a graphic presentation of weather along your route or round your flying area on a map, programmes your iOS/Android/windows tablet/phone as your GPS, etc. I usually plan the night before, then do a quick "refresh" of weather and notams before setting off to the airfield.
Don't be embarrased by taking your time doing the checks - but perhaps a "checklist" for the "other stuff" like water bottle, etc, might help you develop a systematic approach to those actions, too.
Use a multi-compartment flying bag, keep all your stuff in it and learn where in it you are going to keep each item so you can go straight to it.
As I have my own aircradft, I always refuel it when I get back at the end of the flight so it is ready for a quick getaway on the next flight - time saved before setting off is always more valuable than time before driving back home when you return.#
HTH