We procrastinate for one simple reason.

We don't see the consequences very clearly. If someone could invent the machine that would show us a movie of what our life could have been, we would be in shock. Imagine if a few years ago when you decided to go on that diet or start working out at the gym, you actually had done it (and stuck to it). What would your body look like today?

 I bet it would look amazing.
Imagine if a few years ago when you had decided to read more and study how to make more money, you actually had done it (and stuck to it).
What would your bank account look like today? I bet you would have a hell of a lot more saved up.
No one has yet invented that machine to show us that parallel universe where we hadn't procrastinated.

The good news is that our brains are powerful enough to do the projections for us.

Try this: think of someone you admire, someone in better shape, someone making great money, and imagine if their life was yours.
Then be brave and make the leap.
I bet the main difference between them and you is they didn't procrastinate as much as you have.
Use that realization to turn the ship around.
Time is like a mafia loan shark - just less forgiving.
It waits for no one.
See your new future by projecting out multiple outcomes to your life.
Be like a chess master, see multiple moves deep.
Don't be afraid to honestly admit that you have missed out on some big things.
But be optimistic enough to see the light at the end of the tunnel on an amazing future if you rise to the occasion.
This will change your life.