So for our packing list, on a normal 9x11 piece of paper we (wife and I) have printed a list of all our scuba gear (and related gear) we own. It is laminated and we just use a grease pencil when packing stuff. Nothing gets check marked unless is went in the bag, the list can be kind of stupid at times, dive light... check, dive light 2...check...dive light 1 batteries...check...dive light 1 battery test...check... i think you get the idea. It takes us longer getting ready for trips and all that but we know we have everything, it works, and exactly what we don't have. Likewise when we are cleaning it and putting it back into storage we erase the marks on thing at a time, reg needs to be serviced okay don't erase it and add a quick note. That way next time we look at the storage area we can quickly account for it. For pre-dives I have a notecard that is laminated that is similar to GUE EDGE but think I might steal that now.