As her house manners improve, her greatest reward can be to receive more freedom. If a puppy complains loudly about confinement, do not release her immediately or she will get louder the next time. Most puppies would rather race around like wild things than sit quietly by your side. Your puppy should not be allowed or encouraged to do anything now that you would not like when she's fully grown. Rewarding her for good behavior increases the likelihood of it recurring.
Rewards come in many forms.
For some puppies, your eye contact is all that is needed to motivate them to mischief. Other puppies may find rewards in your cat's litterbox. Attention or eye contact, vocal praise and petting, edible stuff, etc. are all forms of rewards for a puppy. Timing a reward to coincide with a behavior you like should occur during or immediately after the desired behavior. Correcting a behavior should also occur within this time frame.