Q:

How to Propose an Idea as an Indie to a Big Company?

Let's say that we've got a good idea/design for a game, but we can't develop it on our own due to our beginner knowledge and skills, so instead we want to propose/sell/give the idea to one of the big publishing companies like Bandai, Ubisoft and Square Enix. Is it possible for beginners to propose ideas for big companies? and if so then how? please we need a detailed answer if possible. Thanx in advance.
*Note: we're NOT saying that we want to be employees in the company, what we mean it is more like working together with the company in the way that we give them the idea of the game and they develop it and then both sides benefit.

A:

This can't be done, sorry. Big companies already have a backlog of ideas that might be great. Even small companies do. Additional ideas are pretty much worthless.
You need way more than an idea if you want to sell it. Generally the minimum that's required is a prototype and a business plan. For beginners I'd change the minimum requirement to a working and playable prototype and a functional development team, in addition to a business plan.

A:

Ideas alone are worthless. value = idea * execution. The best idea with 0 execution has a value of 0.
The reason is that nobody can tell if an idea which only exists on paper would be a commercially viable game. Not unless it's something formulaic which guarantees moderate sales if you throw enough budget at it. But everyone can come up with a concept for yet another first person shooter, GTA clone or grindy MMORPG. They don't need you for that. 
If you have a novel idea, you have to prove that it will work. And the only way to do that is by actually turning it into a game and showing that there is interest.

Create a playable prototype. It doesn't need to be pretty, it doesn't need to run well and it doesn't need to have much content. All that matters is that it demonstrates what's new and special about your game idea.
Publish it (as early access alpha for money if it is worth it, or for free if you have to)
Generate lots of hype and groom a community
Make it apparent that people like playing your idea and would be willing to pay for it if turned into a game with proper production values, but that you lack the resources for developing it
Get into contact with publishers

There is quite a long list of games with niche game concepts which started as small indie games and then got bought up by larger publishers after they had shown that their wacky idea has market potential.

