How do I present an idea without a patent and still protect myself?

In general, without a patent, you will be unable to prevent people from copying a product you manufacture and sell, or a service you provide to the public. While the product or service is being developed, you might be able to protect the idea that gave rise to it using trade secret protection. For example, when attempting to look for investors or when engaging with developers, you can request that people sign a nondisclosure agreement (NDA) by which they promise to keep your new idea a secret.