Avoid thick brush. Contrary to popular belief, bears can see almost as well as people, but trust their noses much more than their eyes or ears. Always let bears know you are there. Give bears plenty of room. If you stray within that zone, a bear may react aggressively.
Bears have only about six months to build up fat reserves for their long winter hibernation.
Don't let them learn human food or garbage is an easy meal. It is both foolish and illegal to feed bears, either on purpose or by leaving food or garbage that attracts them. Cook away from your tent. Store all food away from your campsite. Hang food out of reach of bears if possible.