How do you train your dragon how to get all dragons?

how to get all dragons is easy ,not exactly quick but easy all you have to do is beat each tournament one after another and after each tournament you beat you unlock one dragon but you need to go and grab food for it by battling wild dragons when you have enough food your game will say quest complete then you go see gobber and he will tell you to go to the dragon pen you pick an empty space then a scroll will appear with the dragons you already have then tap on the new dragons name its picture will appear in the empty space you chose tap on the new picture exit the pen then it will ask you to customize your dragon then when your through customizing and give your new dragon a name exit the dragon pen and there you go