There are many benefits of enhancing peripherial vision. You can practice and enhance the skills in situations like...
Walking, Car dealerships when you're looking for the right car. Bookshops for picking up interesting reading. Fruit markets for best buys of quality fruit. Produce stalls and street markets where everyone sells similar products (gives you a chance to price the stuff before making eye contact with the vendors.)
Places of amusement where kids knee highi to a grasshopper usually run amoke, saves you getting bowled over like a ten pin when they come from side one. Bush walking, night walking, enjoy the view while conserving energy also allows you to get closer to some animals, it they think you didn't see them.
When practicing do it for a few minutes and then let go. If you do it once or twice a day for a while you probably start noticing that you do it non consciously. Your mind seems to discover benefits of seeing more so it starts doing it more. At least it did by me I experimented with it many years ago notice that I have a wider field of vision than most.
Alex