Togashi Jump Ryu (a booklet and DVD series filled with interview by mangaka to inspire people) summary, all credit to Sandman from Arlong Park.
[After becoming professional mangaka]
The first manga serialization for him was Ten de Showaru Cupid ("An Ill-tempered Cupid in Heaven"). It became pretty famous, but it finished earlier than expected (chapter 32). Togashi now regrets that he should have prepared a rough plot till the finale before serialization.
2-3 months after finishing his first serialization, new ideas for next manga came to his mind one after another. Then He started Yu Yu Hakusho soon.
Togashi dsecided to focus on the occult and battle in Yu Yu Hakusho since both of them were his favorite genres.
Editor told him that Toagshi is good at creating a story. Togashi was glad to hear that, but at the same time, he thought it wasn't enough in order to maintain great popularity for more than 30 chapters. That's why Yu Yu Hakusho turned into battle manga and made a great success.
Editors in Shueisha consider it is one of the greatest role models to turn a manga which ends in each single story into battle manga. The role model for Togashi was "Kinnikuman" ("Muscle Man"). It started as comedy manga and then turned into battle manga, which Togashi believes can entertain shounen in terms of both surprise and excitement.
One year after he finished Yu Yu Hakusho in 1994, Togashi suggested his editor that he would like to draw manga that would NOT become much popular. This is because he wanted to show various aspects of his personality as mangaka to his audience. Togashi believed he had already drawn traditonl Shounen manga to the best of his ability in Yu Yu Hakusho.
Togashi also told his editor that he would start traditional manga again after he finished "Level E". Editor accepted it.
In "Level E", Togashi was going to finish stories in each chapter, but Prince Baka (stupid prince) became popular as opposed to his expectations. Thus, he decided to make Prince Baka the protagonist of Level E. The prince had complicated personality which always went beyond everyone's imagination, so Togashi had difficulty in creating a story.
Having finished Level E,
Togashi started Hunter Hunter. He keeps in mind that he should change his style in each arc so that his audience can be surprised.
Togashi considers character's personality is sometimes important than story. The ending of Chimera Ant arc was not what he expected at first. He makes a simulation about how his characters will talk with each other and take an action in specified situations, which allows his audience to feel as if his characters really exist.
Togashi loves professional slang. For example, his characters call "turn over" when they visit websites. Also, he shows detailed concept of Nen as if it exists as some kind of martial arts in real world.
Togashi tends to show some rules to his audience at first such as Greed Island arc. He enjoys the process finding system bugs or shortcuts in the rules to go beyond expectations of audience.
In Chimera Ant arc, Togashi enjoyed making a super long list as to how his characters would take actions since 10 days before invasion in Royal Palace. He wanted to draw characters in desperate situations taking an unexpected action when they came across someone accidentally. Editor gives exmaples such as encounters between Morel and Shaiapouf/ Killua and Meleoron.
Togashi has been attracted by dirty side rather than beautiful side ever since he was a junior high school student. Editor considers Mukuro in Yu Yu Hakusho is one of the typical examples.
About drawing style, Togashi decided to draw Yu Yu Hakusho impressively and Level E realistically. In Hunter Hunter, he keeps in mind that he should not use screentones as possible as he can.
Togashi doesn't specify detailed personality of boss characters from the beginning. For example, Toguro in Yu Yu Hakusho was just a bodyguard at first, but his personality gradually became more attractive as his grudge against Genkai was revealed. About boss characters' appearances, he enjoys making them complicated since boss characters don't make much appearances.
While Togashi is drawing manga, he listens to TV show ad enjoys talking about it with his assistants.
Togashi considers himself not being good at drawing color spreads.
-Togashi memorises facial expressions ot characters in other mangas. One of his favorite book is "Facial Expressions" written by Mark Simon.
There are 5 assistants in his studio.
Togashi thinks of Akira Toriyama as a god. He has Dragon Ball 30th book.
On Togashi's desk, there is some manuscripts of a fight betweemn Hisoka and Kastro which he considers as bad quality. He pays attention in order not to repeat the same error. Togashi also says that people on internet fandom were embarrassed with the chapter at that time. lol
The previous editor says, "Togashi-sensei is very gentle. He remembers what editors said in the past and sometimes bothered to be worried about us."
Editor thinks Togashi resembles Gin Freecss in terms of personality. HAHAHAHA
An editor says he was scolded by Togashi only once when he changed words in manga a bit without permission.
Togashi sticks to every single word in manga. He even doens't want to use various fonts since he is always confident of his words being interesting.
Togashi's message to mangaka beginners:
"Keep in mind about audience. Make every effort to go beyond their expectations".
I found this on Reddit:
https://www.reddit.com/r/HunterXHunter/comments/5ayxlu/togashis_jump_ryu_content_summary/
Bold what I thought were the best bits.