You are suppose to buy units for gold(you get 100 gold per each turn + 50 gold for each mine unity you have), you can access to shop by pressing the shop icon or the spell shop by pressing the bottle next to the shop icon. Then use those units to kill the opponent(by tapping on them you can move them and/or attack). You pass the turn to the other player by pressing the "space" key or by pressing the player 1/2 image. The game is made to be played with 2 people and there are tons of different strategies to try out! I hope this helped and enjoy!