RE: Shamanism - what you should know while looking for sacred medicine and guidance

A real shaman would never call themselves 'shaman'. Also, you need to be guided by your intuition mostly - if anything doesn't click with your moral compass, then probably a man is a fraud.
Alternatively you may ask for opinions if the person is well known in arounding society. Personally I know just one guy I can describe as shaman - he's decent, modest and pure of heart, brave, and always willing to help.