Hello,
I have finally finished my windowfarm and …
instantly buil a second one.
In about two weeks, I’ll build a big one at school,
but I haven’t even figured everything out for my own windowfarm.
One of my questions: How can I easily make my own nutrients?
Thanks.

There is no easy way to make your own nutrients. Home made nutrients are typically fish waste from aquaponics setups, or worm tea from composting.
There is a good blog post about a nicely done worm farm from @nnesbitt: http://our.windowfarms.org/2012/01/25/completed-worm-farm/
it is very difficult because they require many individual materials in precise dosage think is best to use some trademarks