(Even Ben Franklin had problems.)
First – Visit the Patent Office website for information about invention promoters. See, for example, https://www.uspto.gov/sites/default/files/documents/ScamPrevent.pdf
Second – Seek an inexpensive consultation with someone experienced in business development and patent/trademark law. Get informed about invention protection, prototype development, marketing, finance, and business development. There are many patent lawyers who worked in engineering and business (such as myself) before taking the patent test and going to law school. Everyone likes to teach, and you’ll learn how to develop your invention, spend your money and time wisely, and develop a trusting relationship for future leads.
Third – Learn from prospective customers: know which features they want, and how much they’ll pay, that knowledge will help you avoid wasted money and time.
Fourth – Learn more about finance so you’ll know whether you’ll make a profit before signing contracts for production, storage, shipping, etc.
Fifth – Go low and slow: Avoid loss of your idea and costly mistakes, such as obsolete products, useless websites, and recalls.
Sixth - Continue to consult with trusted advised. Spending a little money can save a lot of money and problems.
Good Luck.
(Image from Wiki/ Bureau of Engraving and Printing)