If you want help, I can get Marvin Weinberger (founder of patented tools company InnovationFactory.com) on a call - I won't charge extra, since I'll just be facilitating the conversation. Let me know if you want me to set that up.
In terms of prototyping, it depends on the product. If you let me know on the call I'll follow up with resources. For example, if you need a simple, small prototype, you might be able to build it yourself in a local facility (ie: NextFab in Philadelphia). If it's more advanced, there are prototyping resources out there, but they vary based on the type of product.
For simplicity sakes, try Quirky.com
For DIY: first step is being afraid of sharing your ideas. Research has proved that ideas are a revolving cycle among many, before you had it chances are a few people already did and didn't pursue it or failed at it. It seems people don't typically steal ideas, because they are hard to pursue, they don't instantly mean wealth, and thus don't.
But what is guaranteed is that if you don't share your ideas with others, you will too fail in bringing them to life.
Parenting in itself costs a lot of time and money, depending on the idea or "invention" you might better off producing and implementing with a growth hack marketing effort for quick adoption and sales and through sales fund your patenting. Is risky but is often done. First to market goes a long way, sometimes more than parents themselves because a clever firm will always tweak to work around that. - take a what's going on with GoPro right now...
God bless and best of luck!
If this is a physical product that you're talking about, for the prototype, hire a mechanical engineer. I know several which specialize in startups and prototyping.
A quality engineer will not only have experience in the processes your product will need to be prototyped AND mass produced, after you have proved your concept, they will be able to provide you with REAL DFM (Design For Manufacturing), a BOM (Bill of Materials) and a PRD (Product Requirements Document).
In other words, everything you need to contact manufacturers and produce your product. Even if you are planning on licensing your idea or just looking for funding, actually knowing a little about how to make your product will go a long way.
Most mechanical engineers know and can present you to independent electrical engineers and other experts to help bring your idea to life.
This does require an investment but, if you have done your preliminary market research you should have a feel if the benefits are worth the risk.
Before even thinking about a patent, consult an IP lawyer. Just Google some in your area and call for an initial interview. You may be surprised to find that maybe you don't need to worry about a patent right away. I've done some eye opening interviews with IP lawyers on this subject.
Ask them the question, "when am I not ready for a patent?"
Here are a few links to articles I've written on both of these subjects...
I hope these help!