My only real suggestion would be to get a bigger tank. A 10 gallon won't even last you a year, with a healthy, growing red-eared slider, and not many aquariums will be suitable at all for a full grown adult... so make sure you're planning for the long term. Red-eared sliders are a hefty investment, and among the most dumped reptile pets, because people don't think about how big they get when they see this cute little turtle in the pet store, and are unable to house them once they grow. Oh, and make sure you get quality UV lighting.
She sits in her corner, singing herself to sleep.
Wrapped in all of the promises, that no one seems to keep.