Depending on which deck you use, there's a few options: the Duo Deck you need to alternate Magical and Physical attacks to gain lots of Mana, then use the Mana to activate your Top's ability (+1 Burn) each turn. The Mental Deck you need to manage your Deck and Discard pile to get the optimal damage from your Garbage Day and Inner Peace. Also, the Stella card not only heals 10 HP, but also removes 1 🔥 Burn, so prioritize using that card on a Burned outfit.
Alternatively, in the full game you can customize your deck and create a new combo around cards not available in the demo ✨ In the next Demo, I'll be switching the Decks up with different cards and abilities. Hope it helps!