Ok so its not just placing your ADA in an ADA wallet keeping it there and get awarded ADA in return..
If you are feeling doubt and why don't you just visit ADA's main forum directly?
https://forum.cardano.org/t/how-to-stake-with-ada/6903/5Someone has asked this question and there was a lot of interesting answers from ADA fans.
I guess that will be useful for you but in my understand about that just like put and lock your amount in staking address and then you will receive your interest.