Seishin-teki kyôyô is a spiritual refinement technique in ninjutsu.

Points for spiritual refinement
Knowing one's self
Knowing nature
Destiny (can be translated as calling)
Harmony
The Heart
The Eye
Love

Nobody can use the bathroom for you; you must relieve your suffering in your own way. If you are done relieving your suffering, then your mind will be a polished mind, like a mirror, it will reflect clearly on the moment, undistracted by your needs.

Ways to achieve spiritual Refinement:
1). Unblock your chakras.
2). Achieve enligtenment through countless hours of meditation
3). Know yourself
4). Know nature
5). Learn the 9 Cutting fingers, DO them live by them
6). Detach yourself from worldly possesions.
7). Make your Mind Body and Spirit One.

 

Onshin Tongyo no Jutsu is techniques for concealment and escape.  The field craft related to this topic are for the wilderness as well as the busy streets.  If is important in today’s society to learn to move through an environment without being noticed.

Everywhere you go there are cameras.  When you drive or walk into major stores or malls you are being filmed. Moving through an environment without drawing attention is difficult these days.  The skills to blend and work in this environment are important.  These skills were regarded as the highest level of techniques within Ninjutsu. They included hiding and camouflage.
yojutsu ten kan ho was making the ancient Ninja appear to be something or someone else – such as a monk, traveling actor, or a gardener. We can use these skills to appear as a person who should be in a particular environment. The Shinobi can use these skills to move around in an area gaining better access in places and information. Choho or intelligence gathering is an important part of every Chunin's training. Before a person can even enter into Choho training they must be skilled in Onshin Tongyo no Jutsu.

We, as a society, have separated ourselves from nature.  We understand concrete and asphalt better then we understand earth and sky. The problem with survival is that we carry our separation with us when we enter the wilderness. If I were to ask the normal person to go on a 3 day hike they would pack 50 lbs of gear and complain about having to ruff it.

The first level of training is to become comfortable with nature in all it’s seasons. Learn to go out into the wilderness with less equipment each trip.  The best way to learn survival is to take a 3 day trip. Inventory everything that you deemed necessary to survive for 72 hours. Over the next few months take weekend trips and learn how to survive without your lifeline to society. 
There are skills that need to be mastered in order to survive in the wilderness.  These skills must be praticed not read about.Proper Mindset
 Shelter
Fire Starting
 Safe Water
 Hunting, Fishing, Cooking
 Flint Knapping
 Orienteering

Nyukyo no jutsu involved the correct use of timing to make entry.  Here is an example of proper timing. Every secure building that I have found has an outdoor smoking area. If I cannot get past the guard to enter then I drive around the building and find the smoking area. Dress like an office worker and clip on a properly colored name bade that is reversed (so that no one can see it isn’t real).  Wait for the crowd that is outside to be almost finished smoking and
walk up to the group and pull out a cigarette and smoke. Make small talk with the others and look at their name tags to get their names. Once that group goes in wait for the next group to come out (won’t take long). When they are done smoking wait for them to use their key card to enter the building and follow them in. If someone stops you tell them you are with (drop name of person on name badge) and you have a meeting in 5 minutes and you had to get a quick smoke. This technique has never failed to give me access to a secure building. Note the tools I needed, proper business attire, smoking paraphernalia, fake name badges and maybe a folder. This is just an example of timing there are many other techniques that cannot be covered online.
Monomi no jutsu is finding weakness in defenses. Using the example above by noticing the smoking area as not being guarded you discover their weakness.  You need to notice cameras and the other ways someone might enter an area.

Nyudaki no jutsu is finding psychological weakness. By finding a reason for being in that place at that time trying to enter you creates a psychological reason to pass. When challenged giving the story with confidence and continuing to move as though no one would question you, gives you access.
Yoji-gakure is distraction. The smoking was the distraction. People accept you as part of their smoking group when they see the cigarette.  There are also physical distraction, such as a car accident or someone coming in to distract the guard with a request for help.

oei-on jutsu is erasing light and sound. This is a field study topic. It requires hands on practice in order to move silently.  Working in the dark can also be tricky due to unsure footing. Combine these techniques with a time limit to cover an area and you will gain a wonderful skill.