Ask HN: How to get started with your idea?

How do you guys get started with your ideas? I have an idea that I believe might have a potential in the country I live in. But I'm afraid at the same time that it will not work because there are few companies that is well established and does the same. But my idea is somewhat different and better, while the old well established ones are old, not innovative and has been the same since they have started with very bad user experiences. Their success is dependent on the fact that they have contacts and access to companies and organizations which I do not have access to because they have been in the game for a long time. Should I press on with my idea? or should I just leave it alone? According to my co-founder/friend my idea will never work because the users will never leave the well established ones for something new no matter how much it suck