Advice on Freelancing

I’m a salaried furniture / millwork designer and I’d like to try doing some freelance work.
I have some developed designs I’d like to market to manufacturers and I’m wondering if anybody can help me with advice.
What’s the best way to approach manufacturers? How do I pitch my design concept without giving the idea away? What’s the most common arrangements for payments? Any tips or info would be greatly appreciated.

i would suggest that you might research how others, Marc Newson comes to mind, have done this…i suspect that like most anything else it will take 10% talent, 90% butt busting hard work/persistance and a stroke of luck…