One spaceship with a maximum speed of at least half the speed of light.
Some Exotic matter capable of holding open a wormhole.
An actual wormhole to open up.
30 years of free time.
Create a wormhole and prop it open with the exotic matter. This is the hard part, because no one really knows how to build a wormhole or where to get exotic matter. It's not like you can go down to the store and buy a kit. You'll have to work on that part.
Attach one part of the worm hole to your ship and leave the other part on earth. Then fly off in your space ship to some where around pluto and take a six year holiday.
Return to earth. When you get there, you will be about 30 years younger than every one you know. Attach the other end of the worm hole to the earth again. When you walk through the wormhole you'll come out at the exact moment you left.
Take a holiday with all the admission money you got from your time machine.
Congratulations, You just built the worlds first time machine!