Why bother to use Anki in the first place if you can quickly access the information in your Zettelkasten? Because quick access to memory is at the foundation of creative thought and problem-solving. It enables speed in associative thinking to see patterns, in ways not possible if you need to keep routinely looking up information.
Anki guarantees that you will remember something, with minimal effort, and remembering becomes a choice with Anki.
Zettelkasten should be the source of Anki cards. As Permanent notes are already atomic, concise, and written in your own words, they are good candidates for Anki cards.
Do not create Anki cards for all your notes. You should create Anki cards only for notes that you want to memorize forever, so be picky about them.
But generally speaking, if some fact or information is worth 5 minutes of your life, move it to Anki. Why 5 minutes? Because it is the approximate amount of total review time you will spend over the entire 20 years.
Permanent notes require additional processing before going to Anki. You should create Anki cards in form of questions or with Cloze Deletions.
I recommend to adhere to the following principles when creating Anki cards:
Learn before you memorize
Learning the material should come before creating Anki cards and memorizing them, not during the review. It is better to spend extra time learning and creating high-quality cards than trying to memorize badly written cards you do not even understand.
Memorize basics and main principles first
Memorizing basics is the most important because you build all your further knowledge on them.
Keep cards short and simple
Make most Anki questions and answers as atomic as possible. Simple cards are easier to review and remember. if you create complex cards with long texts, you will struggle every time you review them and spend more time. Creating several short simple cards is better than one big complex card.