Theres not much to do here, but you can choose the tribe and other info for your parents as well as for your mate and your dragonets(If you want your OC to have a mate and dragonet(s) ). You could also choose which traits your children have. (EX: the dragonet is a hybrid of a Rainwing and a Sandwing, they look more Rainwing  than Sandwing.) And you could also make your mate a hybrid as well but it might be more difficult if you and your mate are both hybrids. And for your dragonet make sure not to make them too overpowered, like if it was a Rainwing/Sandwing hybrid, you'd have to choose venom or fire. It can't be both. It would be overpowered and kinda cheating. Speaking genetically, if you had a Rainwing parent and a Sandwing parent, the abilities would probably cancel out and you wouldn't have any ability or it would be very weak. But if you had a Sandwing/Nightwing hybrid you'd definitely have fire, it won't be strong or weaker. Just because both of your parents are different tribes with fire doesn't mean it makes your fire stronger. Like a Sandwing/Sandwing dragon has the same amount of fire as any other Sandwing/Sandwing dragon.