* Research faster interstellar travel, especially using something like a Buzzard engine to utilize interstellar hydrogen as resection mass. Required nuclear fusion power plants / engines and ridiculously strong magnetic fields; both seem attainable.
* Slow down human body metabolism and allow humans to stay asleep at near-freezing temperatures for a long time. If bears and chipmunks can do it, chances are humans could learn it, too.
* Invent sets of machines that can reliably self-replicate, given most basic inputs like minerals, water, and sunlight. Advanced semiconductors are going to be the tricky part.
* Study psychology, sociology, history, game theory, etc, so that the early society that will form on the new planet, isolated from Earth, would avoid at least some of the pitfalls that plagued human history on its home planet.
Also, it won't work unless scaled up to the sort of thing only a Kardashev type II could do — 4000 km diameter — and at that level you've got other options that mean they probably won't:
>Slow down human body metabolism and allow humans to stay asleep at near-freezing temperatures for a long time. If bears and chipmunks can do it, chances are humans could learn it, too.
The thing is - our current bodies can't live in space for long. So either we will have to build new bodies for us somehow or build a ship that can have gravity inside and protection from space outside (and we are talking about very heavy protection here)
In any other case there is no point in slowing down metabolism or whatever. You will die rather soon.
* Slow down human body metabolism and allow humans to stay asleep at near-freezing temperatures for a long time. If bears and chipmunks can do it, chances are humans could learn it, too.
* Invent sets of machines that can reliably self-replicate, given most basic inputs like minerals, water, and sunlight. Advanced semiconductors are going to be the tricky part.
* Study psychology, sociology, history, game theory, etc, so that the early society that will form on the new planet, isolated from Earth, would avoid at least some of the pitfalls that plagued human history on its home planet.