You can't, but that won't stop you and me from trying, at least a little.
We (Humans, americans, at least "other people like me") like to buy things. But we should do more than just buy things.
Experiences can have a much bigger impact on people’s happiness than things, and a big part of that happiness lies in looking forward to the experience that you are going to have.
This article is long, but it is worth a read.
If you have $100 to spend on something, schedule something you will look forward to for a week or a month. Looking forward to something is as important as enjoying the thing itself.
If you want to have 4x the fun, invite someone along.