Antiocheian writes: Stephen Hawking describes, in the Daily Mail, how to build a time machine. "All you need is a wormhole, the Large Hadron Collider or a rocket that goes really, really fast".
The article deals with potential issues, such as time tunnels being a bit small for a human to enter: a billion-trillion-trillionths of a centimetre. It also explains what would follow a successful launch in a wormhole:
"The initial acceleration would be gentle because the ship would be so big and heavy. But gradually it would pick up speed and soon would be covering massive distances. In one week it would have reached the outer planets. After two years it would reach half-light speed and be far outside our solar system. Two years later it would be traveling at 90 per cent of the speed of light. Around 30 trillion miles away from Earth, and four years after launch, the ship would begin to travel in time. For every hour of time on the ship, two would pass on Earth. A similar situation to the spaceship that orbited the massive black hole. After another two years of full thrust the ship would reach its top speed, 99 per cent of the speed of light. At this speed, a single day on board is a whole year of Earth time. Our ship would be truly flying into the future."