Question The most important Decision!

I bet his brain is the wordiest medium of them all xD

 

Eeh... even though this site is dedicated to novel, looking at review page all complain about info dump I don't recommend starting from novel.
Novel --->Manga---->Anime
No, this is not the order of reading/watching this series. But the order of how much info dump and details you have to see in each.

1. Novel since it's just writing with occasional images, the world building AND information on war reference and philosophy is mentioned and explained very clearly. For example, you can only find how magic in Youjo Senki works in novel and how the war progress in detail. However when you start reading the prologue, be prepared to be confused as in this first person POV novel, Tanya talks about prison experiment and Chicago's school of economy instead of herself. The prologue is like a thesis in light novel format, certainly an original way to start your story.
2. Manga cut down the info dump, Toujo Chika certainly did her best in that front. However it's clear she is juggling between putting enough reference Tanya bring up frequently in novel and not overloading her manga with it. Personally I recommend you to start from manga, because it gives you decent idea about the world of Youjo Senki before seeing less detailed anime and too detailed novel. Unfortunately, the manga just reached Norden arc by chapter 20. The art is very gorgeous, and each chapter is around fifty pages are feast to your eyes. Though following Carlo Zen's quirk with love for info dump... Toujo Chika likes to draw animal puppet occasionally to narrate war strategy or Tanya's monologue. It's a bit mood breaking sometimes, but it's good and updated regularly.
3. The ANIME! Some says the art is cringe worthy... but it's not so bad after two to three episodes. However, NUTS studio changes some stuff and arranging the episode not in order. First half of the season focus on action, so there's not much info about world building. Anime lacks details, but it does grab your attention with music, action and art. The anime stops explaining the world of Youjo Senki with little background of the way they fought, and the explanation about their magic is nonexistent aside it exist and there's science behind it.
   Also, the anime skips a lot of scenes from LN and manga. Why? The limited time for once, and... the manga and LN is pretty realistic in how the military launch each of their operation, there's pre-mission test, meetings, politics inside their rank...
   I advice to watch the anime after manga and before light novel.

Of course, you can go up in order of how much mumbo jumbo about war and philosophy in each media if you want. Because the way LN is written, the three medias almost feel like different series ^^; So after reading my description above, you can decide yourself where to start to get to know our favorite hitler-loli.

Ha ha ha we wish... I don't want to know what's going through Carlo Zen's head though LOL, I mean the prologue he wrote discourage me from finding out LOL

 

I think It's a lot easier to watch the Anime, read the manga for comparison and follow the novel for an in-depth matrix ride.

 

Be prepared if u wan to read the novel first cox it long, like double or triple the length of normal LN xD