Changes

Although this may seem to be a small mathermatter, types and colour of clothing are very important. Try to wear light coloured clothes, and have your non-thumbing hand visible since light coloured clothes inspire more trust than darker clothes. Also, if the weather permits it, try to keep your forearms visible. If people can see your handsand arms, they'll be less likely to see you as a threat, or as someone trying to conceal something.