When you get a young dragon it is bound to evolve. All you have to do is get it to the right level and it will. But how do you decide which element you want to evolve this dragon into? What happens if you don't like your choices?
You don't get choose exactly how a dragon will evolve. Generally it's at random. However, there is a way to effect the outcome of the results. It may already be to late for you though. Here's how it works: When you evolve a young dragon it will evolve into the same element as the Elem Pedras that you have. So basically, if you chose the Elem Pedra of Wind, all of your dragons will evolve into a Thunder Dragon.
There are some exceptions to the rule though. There are the two special types of dragons thought that will evolve a certain way regardless of what Elem Pedras you have. They are the two other elements. Virtue and Bane. In some special cases, your young dragon will evolve into a Black Dragon or a Platinum Dragon, no matter which Elem Pedras you have.
But say you took the Elem Pedra of Fire, and you want a Green Dragon. There are two ways of going about this. You can manually go to the certain levels to find, a catch a wild green dragon, or a wild Ahzi Dahaka, but there is a simpler way. You can get different types of Dragons by finding all the different Elem Pedras. Perhaps you didn't know you could get all the Elem Pedras? Well, If you'd like to learn how you can go about getting every one, you'll have to consult the Elem Pedra's guide.
And so you can get every Elem Pedra so that you have a random chance of getting a new kind of dragon, or you can do it differently. Just get the Elem Pedras that you need so that you can get the type of dragon you want.
I hope this gives you some insight on how to raise dragons. Head back to the Dragons section by clicking on the link.