Welcome ignoramus! You skipped all the dialogues and now you roam the halls of the academy without a single clue what to do. How do I know? Magic!
Let's start with the most basic thing: Do all your classes! There are not much, and they are needed to find some spells, so do that now. And don't skip the dialogues again, there are requirements to start the next level of some classes! Feel free to explore the library or the workshop for some spells or useful items, when no classes take place.
Done? Great! Next you probably want to find some more spells, if not all. And don't forget to #enchant your clothes. These will probably happen simultaneously either way, so feel free to allot the time on your own.
Get all the spells
If you want to know what spells are there to find, take a look at the complete spell list. All the base spells are found in the library (except those you learned in your classes). The recipes for clothes are usually in the workshop. Some variants are in different places and some can only be obtained through consumables like the fox variant. Also, some spells and recipes are only available during events, so if you struggle to find some missing spells, take a look at the corresponding site.
Spells can only be found while "exploring". "Searching" will only yield clothes.
Enchant your clothes
You've been transformed into a tiny doll too many times and now you want your revenge? Excellent! Have a look at Enchantments. Everything worth knowing is in there.
Hm, I guess that's it. Go out and find some nice, juicy victims!