Kogusoku

A little bit of budō triva: Fukuda sensei's grandfather was Fukuda Hachinosuke Fukuda was a bushi and Kanō Jigorō's (The founder of jūdō) original teacher in Tenjin Shinyō-ryū jūjutsu. Almost a historical full circle.

What I picked up from my koryū bujutsu teachers in Japan was to use rubbing alcohol to cleanse the blade after doing tameshigiri, wipe clean and dry and then apply sword oil (Tōyu) afterwards to ensure that the steel didn't rust. Wipe the weapon clean and oil it after every training session and keep the weapon in its saya when not in use.

I learned it very early on, when I was a nidan in jūdō while living in Japan. It really depends on the teacher you are studying with. Some go by the book and have you wait until you are godan (5th dan), while others are more relaxed and accomodating, providing you actually show a proper, respectful interest in learning the skill set in question.