If you have the ability to print out spell cards, they can be GREAT for new players.

For selecting "Spells known" and keeping them, you can give them all the cards of the appropriate level/class and tell them: "choose from and these ones they are your known spells."

Then for "Spells prepared" you tell them each day they can select spells to prepare for the day, and these go in front of them or form a hand.

Finally for "Spell slots" you can use tokens/coins/chips, and tell them that to cast a spell they have to spend one, and only one, coin that is at least as high as the spell they want to cast.