A suggestion: don't do it, use the resources to create a more sustainable colony on earth.

Probably your First Colony on Mars, should be inside the extinct volcano of Olympus Mons. Seal off the Rim of the Crater, then Pressurize it with breathable air. Crater floor should be sufficient to comfortably populate at least 10,000 people, if not more...

The Earth cannot sustain the current population growth. Either we go all in on colonizing another world or we mandate population control in every country. Good luck doing that.
As far as ideas, do instead of not doing. We have a satellite world ready for colonization just days away instead of years away. We have the technology right now to setup factories on the Moon with unlimited solar energy for a minuscule fraction of what it will cost to do the same on Mars. With what we can learn on the Moon instead of waiting for some new tech that is not developed yet we could be light years ahead by doing instead of not doing.
We have the knowledge and capabilities today to setup factories on the Moon. There are enough raw materials and free energy on the Moon to build and power small cities that could in turn build real space craft instead of flying bubbles of air. The Moon has 1/8 the gravity of the Earth so lifting heavy objects to space is much cheaper then on Earth.
From the Moon we can move out to harvest materials in zero gee which is even more efficient since there is no moving to space at that time. All of these should be milestones before colonizing Mars.
Sending a couple of cheap modules to Mars is only a death sentence to anyone that goes without a real space faring society to support all endeavors in space.
Do it. The real technology comes from improving what we can already do. We have already done the Moon small scale. Now lets do it large scale and really grow our space faring society like we should have done 40 years ago.

@Jon - You cannot meaningfully change the direction of 7 billion mostly selfish people, not even if you had 10x more power than the most powerful person on earth.
@Krisno - Moon has no atmosphere. Space is too dangerous for life without a big shield protecting it. Bigger than we could make.

YIKES! Evil fine-print. If you tell them anything, they get free use of all your intellectual property: for a meagre slim-chance shot at a tiny prize.

@christopher Whether we like it or not space and the challenge of dealing with the problems of space will ensure our future as a species, that is if we ever solve the current problems of humanity that may preempt our species survival on Earth.
We already have people living in space though they are partially protected from dangerous radiation from the Earth's atmosphere which does not protect the Moon. All the requirements to build protective structures are already on the Moon though except for the people to build them minus the initial factory components to start the process. I would even venture that we have the technology to start building the necessary components without people even being on the Moon, at least for the basic structures to protect people once they get there.
All this talk of soliciting public ideas is just wasting time and I think some or all of this is on purpose. You are right that the shield needed is bigger than what a government could make but it is not too big for enterprises to make. The only way we will get into space on a permanent basis is to allow commercialization of space to start. There are countless industries that can make money from exploration and exploitation of space. Let it begin already. Stop holding people back with ideas that it is too hard. The discoveries on earth are more expensive then what can be discovered in outer space. Look at the cost of the LHC and the focused discoveries we might find. Put people in outer space with the same scientific instruments and the discoveries will come much faster and much cheaper.

Read this:
Red Mars (Mars Trilogy)October 1, 1993 by Kim Stanley Robinson (Author)
Contact Hank Green:
He has memorized the trilogy AND he owns the hardback edition Put him in charge of the mission
Relax and enjoy the ride...

Went to site, very complicated to read & see what NASA wants. Not open to General ideas then whittle down for others to Really use or apply, alas.

A Mars colony is great news, but we would have solved most of the colonization problems if we had colonized the moon 40 years ago? It is like we are skipping all the baby steps we should have taken and now we are going to sprint off into a Marathon! There is nothing like a government run space program for putting us behind the 8 Ball!

@Jon:
Okay. Where?