I keep an Excel spreadsheet of all my DIY maintenance work along with a file folder with service reports, receipts, etc. If and when I decide to sell the car I will turn this over to the new owner.
I keep a text file log. For each maintenance I note the date, the kilometers, if it's a schedule maintenance I'll note something like "6mo/8000km maintenance", and then a breakdown of the specific items done (or not, some I'll skip), and comments. I also keep a duotang with all receipts. Typical receipt would be 4 liters 0W20, oil filter and drain plug washer. I typically buy through the dealership's parts department, which helps in that I've got one document with all the items. I'll pencil on the receipt a notation that ties it to the text file log.
I use the Toyota site: Toyota Owners Official Website: Service Coupons, Owners Manuals, Service Scheduling and More, plus annotations in my gas purchase log and receipts in a folder.
The Toyota Owner's site is a good place to keep all of your maintenance records in one place, including your own maintenance. I do this also. The problem with this site is that if you sell the car and the new owner registers the VIN under another name, any third party information is deleted. Toyota's response to this is that they can only verify the dealer maintenance services.
I also use the Toyota Owner's website. It is a great place to do it and allows for easy retrieval by me. If you sell it, you can simply print it out prior to the sale.
Thanks for the tidbit JD, I usually highly recommend the sight as it is a good way for new owner or potential owners to learn about their car's service history but I didn't know the owner entered records would be deleted. That sucks. Oh well like mention earlier, print out before the sale.