I too have forgotten important things. One trip I left my Pedals behind.
I now travel with a laminated check list in the bottom of my handle bar bag. Really helps.
My only advise is enjoy the ride. Take the lesser traveled road. Take your time. That is to say; so what if you don't make 50 miles day. My wife and I average between 20 and 55 miles a day.
We go into every small town we come to. We stop and buy a soda and look around. Lots of interesting things happen. People will talk to you - without fear or worry. They are interested.
We have slept in people front yards. For example, one morning, after spending the evening in this front yard, we were breaking camp discussing where we were going to have breakfast, the people who let us sleep on their land, called out and asked if we wanted bacon or ham with our eggs.
Keep a diary of the highlights.
get some slime tubes and good tires. Practice changing tubes and fixing leaks. Carry extra slime filled tubes. I carry a hand pump and CO2 cartridges. After fixing a tire, I pump it up with the hand pump. Then, I finish filling it with the C02.
I carry lots of water. That is, I usually have one gallon of water at the beginning of a cool day. If the day is going to be in the 80s or greater, I fill my 10 liter MSR bag in addition to the gallon. I often will have to fill the bottles more than once.
You don't want to be short of water.
I also have a PUR Water pump/filter that I carry in one of the pockets of my panniers. It seems that I have to use it once or twice every two years. I change filters at the end of a trip when I used it, because I don't use it often.
On hot days when you are riding through a town, stop at a grocery store and get some frozen fruit. Great nutrition and a great way to cool off.
If the community has a public pool, use it. They usually will let you put your bike inside (so someone won't vandalize it.
