basic idea make a couple signs - stand out by a target - prospect for like minded folks [we have many in pdx] - and hand off your sign for others to voluntarily hold in shifts - even if your signs get put down and left - they will be seen.
perhaps staple some instructions to the signs like [this sign is meant to be held by many others. please hand it off to others to hold near [your target]. explaining the idea, yadda yadda.
what do we think?