I have also designed some products. Let me tell you this issue from my own experience!
First, take out your own product design drawing. If it is of great commercial value, go to the patent office to apply for a patent certificate. Don’t rush to make money first, see if there are related products that have been released. If not, congratulations. You, you have your first patented product.
Secondly, after the patent application is successful, negotiate with similar companies. Because of patent protection, they will not copy your stuff. If you cooperate, you can use the patent as a share, or you can get a commission from selling a product. As much or as little as you like. Sign a cooperation agreement.
(If you need to make this model, first find some basic materials to replace expensive materials, such as mud, wire, etc. Don’t be afraid of being simple and simple, just show the working principle.)