If you are camping in a managed campground, then dispose waste in the designated trash recepticles. Most managed sites will have restroom facilities. If you are camping in a non managed site, or in the wilderness, keep the following tips in mind:
No waste should ever be discarded into a lake, stream or river.
If the ground is not frozen, all body waste and camp refuse should be buried immediately.
Burying your waste immediately will keep flies and bugs from landing on the waste and then contaminating your food.
The smell of food waste will attract wildlife, so disposing of it immediately will cut down on the odor, and will keep uninvited guests from visiting your campsite.
Your waste disposal site should be located well away from your main camp area at least one hundred yards.