The following statements were taken from a very famous main stream scientist's approach to the subject. (for testing arguments and detecting fallacious or fraudulent arguments) I have adapted (but DID NOT change the meaning ) some of the definitions to apply to the Paranormal Community (in simple layman's terms). However, I have left out the ones that did not apply. The principles of the ones I did use can to apply to the scientific approach of just about anything:
1) Wherever possible there must be independent confirmation of the facts. You need more than just yourself to come up with the exact same evidence.
2) Encourage substantive debate on the evidence by knowledgeable proponents of all points of view. All people from the paranormal community regardless of their opinions.
3) Arguments from authority may carry little weight. (in science there are no "authorities". Only the knowledgeable). The Paranormal Investigator has taken a "Belief" a "Blind Faith" (in ghosts) and is trying to prove it scientifically. As we all know, there are no Paranormal Experts. Just explorers like in any other science that is unproven. If someone is telling you they are an expert, then they are trying to sell you something. Most likely themselves. This may offend some but, it is true.
4) Spin more than one hypothesis - don't simply run with the first idea that caught your fancy. I am the only one I know (well, at least I haven't found anyone yet) that goes back to the same exact spot over and over and takes the same photos, recordings etc. I do my best to wait for or recreate the same conditions and then do it all again. Getting something once is nice but will never prove anything.
Example: I have seen an investigation based on noises. Loose pipes, creaky floor boards, etc. were found and they just automatically attributed everything to the things they found and left it at that. End of story. That doesn't tell me or anyone anything.