The point of this is to create deep readers. By going into depth, you can see jokes and hints of foreshadowing. I recommend you use a fan-translated version (onemanga.com) as they don't make as much mistakes as Del Rey. Del Rey does have interesting extras though.
Volume One: (Chapters 1-6 for online scans)
This volume introduces the main character, Negi Springfield, and gives us his entire class of 31 girls. The amount of characters is enormous but not over the top. We are shown all of them slowly and appropriately. For the first few volumes, they will be introduced through having a chapter devoted to them. Through this process, we meet about 15 characters. The later characters will be introduced by having them advance the plot. This guide will tell you which ones you should focus on as you read and what kinda of elements to look out for.
Quick story: Negi has a final task before he can be a great mage: teach japanese school girls english. Pretty much, Negi can not allow anyone to find out he is a mage or else. However he is quickly discovered by the worst person ever: the one person who would want him to removed from his position and have him fail his task.
Nothing amazing so far. Good humor but plenty of fan service which might be a turn off for many. An interesting story though not original yet. This volume isn't story related, just filled with introductions.
Characters: This is what this volume is filled up with setting up the characters, not story (though it is set up a bit). We meet Negi, Asuna, Konoka, Nodoka, and Ayaka (each having a chapter devoted to them). These stand out the most and will be important so its best to understand them now. We do see other characters frequently (Paru, Yue, Anya) but they will come into play later. The above 5 are the main characters for the next couple chapters. Watch the minor characters that pop up frequently though!
Things to pay attention to:
-there is a two paged extra near the beginning which shows all the girls, Negi, Takahata, and Shizuna. This a great way to connect character to their hobby. You might want to notice the girl in the middle: Zazie Rainyday. Foreshadowing?
-Be sure to understand what a magister magi is.
-be aware of Asuna's toughness
-there is an early introduction to the Baka Rangers. They as a whole are very popular characters and will be sure to pop up often enough. You'll see them in the next volume though.
-Negi is looking for his very famous father, Nagi, who is a magister magi.
-there is some mention of Negi's backstory (look where he says he met his father). That is important to look at .
See you in the guide for volume 2!