How exactly do you get sponsors?
You start out with a plan for a project. You then want to present this project and plan to your sponsor of choice. It'll be easier for me to explain with an example.
Say I'm building a new watercooling system and my choice for watercooling is EK. I would setup a project that I have in mind and make a plan of what I'm going to do with my watercooling, down to the last detail. I call up or write to EK and present them my project and that I wish to obtain so and so products for the project.
Now, in order to obtain those products, I pretty much have to use all EK watercooling products in my project (i.e pump, blocks, radiators, fittings) or no dice. In return to getting these products, I have to do something in return for the company, otherwise the companies would go bankrupt handing out products for free to everyone.
So, in return for the products I would have to, for example, show that I'm a dedicated member of a forum in the sense that I've done multiple successful builds, or that I'm an active modding member, etc. Or, that I would test bench, compare, etc the companies products and also provide business for them. That means, I would pretty much need to advertise only this certain company and none of its competitors.
Kind of a long paragraph but that's pretty much how it works.