Here's what has worked for me:

1. Keep the financial potential of an invention in mind. Some things I have come up with are technically interesting, but their commercial value is limited. Since a patent costs so much money to get, it's probably better to focus on technologies with business value only. Some technologies are also buried deep in products and are not easy to detect. For example, I could have invented an efficient algorithm which people can incorporate into their programs. The problem is if it is difficult for me to know when others have put the algorithm into their software, there is no way for me to go after patent infringers. This means it's going to be very difficult for to enforce my patent rights and make money from my invention. In other words, the financial value of my technology/patent might be zero, even though it's a groundbreaking technology.

2. You need persistence; and don't be intimidated. It takes a lot of effort to clearly describe your invention in writing. You'll also be plagued by doubts like: "is this really new? isn't this obvious? hasn't someone thought of this already?" And the sheer amount of innovative inventions that you'll see when you do a prior art search can be intimidating. Just be persistent, and have confidence in your idea. During the patent examination, you might also face a lot of objections from the patent examiner. The patent examiner is just doing his/her job, which is to thoroughly scrutinize every patent application. So don't give up. Just prepare your rebuttal to the best of your ability. Just because a patent examiner raises an objection doesn't mean he/she is right. It just means there is something for you to clarify and explain to the examiner.

3. You're smarter than you think. A common problem with inventors is that once they have thought of an idea, they then think that the idea is trivial or obvious and not worth patenting. Don't fall into this trap! It's only easy because you know how the invention works. Other people may not have put the same amount of thought into it, so it won't be as obvious to them. Sometimes your invention may really be a very simple idea. That's fine too! Just because an idea is simple doesn't mean that it's obvious to others... if it were, someone else would have invented it already. Take the example of the paper clip. It's a ridiculously simple idea, just bend a wire into the paper clip shape. But until the first person did it, no one could see it coming.

4. Simple Inventions: Inventions aren't always about high technology. They can also be about new combinations of things or putting existing inventions to work in new areas. The Post-It is a good example. The adhesive it uses is a high-tech piece of chemical engineering. The paper it uses probably has been treated with some advanced chemical process. But the core invention of the Post-It is simply to apply a strip of adhesive to the paper. That's what it really is: a combination of two existing inventions, to produce a new invention!

5. Simple Inventions: Inventions that sound trivial. silly or embarrasing. Some perfectly good inventions are really simple. In software, it can something as simple as a using a piece of retail store data to extrapolate and project retail inventory needs. It may sound trivial, but the innovation is in its application to a particular business context. The point is: an invention may sound trivial to you, but it could be patentable. If you're wondering if something is patentable, try doing a search of prior art patents. If you see something similar there, then it's probably patentable.

6. Keep it secret. It's easy to get excited about your invention, and you may be tempted to start using it in public, or tell your friends about it. Don't! Before you have filed your patent application, don't use it publically; don't commercialize it; don't put it in a proposal; don't publish it in an academic journal; just don't let other people know about it! This is because in many jurisdictions, once an invention is "in the public domain", you will not be able to patent it. In many countries, if someone else files a patent for your invention before you do, the patent rights actually go to that person! So be careful. If you have to let someone know, make sure they have signed a Non-Disclosure agreement with you. Even then, you're taking a chance. If he/she blabs to the world about your invention, the most you can do is to sue him/her. Your rights to your invention may be lost forever.

7. Make your patent as general as possible. When filing your patent application, don't make your claims too narrow. Try to identify the concept behind your invention and patent that. For example, if you have invented a new projector lamp using a kryptonite lens, don't restrict your patent to claims for a kryptonite project lamp. Instead, generalize your patent to claim the invention of using kryptonite in a lens to focus a beam of light. Then cite the example of a kryptonite projector lamp as an example of the application of your invention. That way, other people can't work around your patent or use your idea in other areas without paying you royalties.