There are many articles that tell you ninja clothes (shinobi shozoku) should be tight-fitting to avoid making noise. The clothes should instead fit your body in a loose style.

Being unnoticed is important for a ninja. Your nightclothes should be dark blue and comfortable. Consider wearing a keikogi, a martial arts training top, and a hakama, or loose fitting formal pants. The bottom parts of your hakama should be tucked into your tabi (ninja boots) and tied with a string for each foot. [1] X Research source

Extend the moving leg forward and use it to feel for any creaky floor boards. Then starting from the outer edge of your foot, ease your weight onto that leg.

The lower you are, the less chance they’ll see you. When ascending stairs, if they are creaky, walk on the side of them, closest to the wall.

The core of Jujutsu is fighting without weapons.

A modern fictitious ninja who incorporates this fighting style is Batman.

You can also seek out further training after receiving a basic martial arts training.

Bring the BS holding hand straight down, accelerating as you bring it down. Make sure it’s powerful enough so that it slips out of your hand. Try not to be too powerful or you won’t have much accuracy. [5] X Research source

Jodan no Kamae. This entails holding the sword overhead at a 45 degree angle. Seigan no Kamae. This technique places the sword handle at hip level with the tip aiming at your adversary’s eyes. Chudan no Kamae. For this, the sword is held at your center, above waist level with the tip pointing to your adversary’s stomach. Hasso no kamae. Have the sword at your side in a manner similar to a baseball bat. Gedan no kamae. The sword handle will be at your hip’s height so the tip aims towards the opponent’s feet.