"The problem with the future is that it keeps turning into the present."
-"Hobbes" in Calvin and Hobbes by Bill Watterson
It's been shown over and over again that we are not very good at long term planning, especially when it comes to our money. There's a whole host of reasons that we seem to struggle to do it, but it boils down to us being tempted by instant gratification over long term security. In other words, you give Present You more benefit than Future You. My guess is that Future You is not happy about this.
It seems, then, that we should find out what Future You has to say.
What Does Future You Look Like?
With technology that we have available to us now, we are able to see what we might look like in the future. Studies have shown that just by seeing what we look like in the future we are able to boost how much we save - some say by 200%! This has the effect of humanizing our future selves, making it less of an abstract concept. You get to see the person.
What you do or do not do today will directly affect this person. That can be enough of a fire to get us to change our behaviors!