Get educated. Know the field you are going into. Don't just get a degree. You are going to have to prove hands on participation if you are looking for millions of dollars. The millionaire mindset is stingy. That's what got them where they are. They are only interested in something with a guarantee of a product.
Establish credibility. Who are you that they should lend you cash? It would be preferable that you are educated in the field. You should have a portfolio with a proposal outlining the project which you desire to spend the money on. It is also pleasant to get other researchers or developers onboard with your notion as that shows that they find you or at least your impression as credible.
Study at the millionaire mindset again. Why should they lend it you? Your project should be developed in a method that it will provide some sort of extensive term societal benefit, such as cancer research. At the very least there should be a cultural benefit such as an archeological excavation.
Get into the millionaire mindset. Why do you require the money? If you wish it to spend frivolously, you are reading the wrong article. If, on the other hand, you are interested in the same tool they are, you might just be onto something. You should have some sort of research or development program in purpose if you are going to try to get into the pockets of the millionaires with money to lend.
Begin to gaze for connections in academic circles. Often this is where you will find lenders for your projects.