Earlier I posted about a basic skill: take initiative! Don't wait for someone else to tell you what to do. Try stuff.
It is exciting when you think that you have finally obtained some research results. It is even more exciting if they seem interesting and potentially important. But, don't fool yourself. They may be wrong! Mistakes happen in research. More often than many want to admit. Furthermore, the more complicated the technique and the system under investigation, the more likely something will go wrong. Murphy's law!
So how do you check your results? I am not sure. There is no simple universal procedure to check results. Just repeating the experiment or calculation is not good enough. You [or the instrument or software...] may be making the same mistake.
Learning to check results is an art and requires patience, discipline, and creativity.
Furthermore, different individuals and different research fields often have quite different standards as to how many different checks one should perform. Some seem to rush to publish once they get an "interesting" result. Others, are very cautious and careful and perform multiple checks.
I am very thankful that many of my collaborators over the years have been more conscientious than me.
For students: here are a few ideas as to some basic checks that one should do.
Compare your results to relevant published work. Make sure you can reproduce earlier work. If not, do you have a good reason to believe you are right and they are wrong.
Compare your results to limits [e.g. weak or strong coupling, for which one can obtain analytical results].
Use different versions of software or numerical methods.
For short programs, write two codes from scratch.
Compare your results to Mathematica or a numerical calculation.
Change the sample, device, material, instrument, or procedure.
Try different basis sets and levels of theory. Don't just do DFT! When possible, benchmark it against smaller systems.
Have different individuals do it independently and see if they get the same result.
What do you think are good procedures for checking results?
When should you quit checking?