But by asking here, how will you know who is giving you the right advice on which advice to follow! [brain asplode]
I think you should just use advice here as starting points and verify yourself that what they're saying is, as best as you can tell, correct.
Using sites linked in profiles isn't necessarily a sign that they know what the're doing (my linked sites aren't sites I work on, though I should really update them with decent ones) but even if they were awesome I have on occasion given 'bad' advice, or at least been lazy with my analysis of the problem, so assuming you took that into account it's still not guaranteed to be good advice every time.
There's obviously the good answers and endorsements on their Q&A profile, but then again, not everybody uses the Q&A much or can just blanket answer every question and pick up a number of Good Answers.
Links to 'official' answers are often the best knowledge the industry as a whole has, beyond experimenting themselves (you may or may not be surprised at what Google would like you to think they can do versus what they can actually do).
So, realistically, you can't. You can just see what looks right and verify to the best of your abilities. Ultimately anything you do is going to come down on your head, so, test or find something 'official' that backs up what's said.