Young Wizard, You must first EQUIP your deck in order to use it. Just like a hat or wand, a deck must be equipped.
To equip items, select them in your backpack & press the hand icon to equip the item. Items that have the little hand icon are what you are currently wearing. Items that have the little dollar icon were purchased with Crowns. Items that are greyed out, you cannot wear.
Once your deck is equipped, you need to put cards in it! Your wand automatically places a number of minor bolt spells in your deck, and amulets will often times put a random spell card in your deck. If you have more than one deck, you can scroll through them by clicking the arrows around the deck title. To put a card inside your deck, simply click on it on the right side of the screen and it will show up in your deck contents. The red circles next to the card shows the max number of copies you can put inside the current deck. The yellow circles show the number of that card that you have already put into your deck.
So equip your deck, fill it with cards, and you'll be well on your way to winning those duels!
