there is no right or wrong way to go about it!
if you are polite and easy to talk to then the farmer will generaly tell you his pest / vermin woes and tales to chikens going missing etc, and then your in!
i peronsally dress normally(no camo)and i have a folder with all my qualifications, FAC & SGC, and more importantly a copy of my BASC insurance...which is usually the deal maker! along with a few photos of stuff i have shot. if they still aint interested after that...they never will be.
i find picking up ground quite easy but then cornwall is a pretty chilled place to live an