Take care of your feet.

Your feet have to support you your entire life.  The average person will walk more than 100,000 miles by the time they are 80 years old.  Your feet aren't like car tires that you can replace every 50,000 miles, they have a life time warranty.  So treat them well.  Pamper them.  Always buy good quality shoes. It might be costly, but it's one of the best investments you can make for yourself.