You don't need loads of stuff to be happy. Like this girl on the picture, although she looks very poor, she seems quite happy to play with the dog. Think about this: you don't need loads of things to be happy.
So if you're in a shop, and you think, let's buy this cool item, please think twice.
Think: do i REALLY need it??
You can also decide to ignore those nice beautiful cool arty things, and save your money for your trip you want to take.