by definition, once u start to trade or offer ur cards-ur plan will be guessed. if others agree to help, great. if not you cant NOT trade or offer if u hv a plan. u dint participate in the chuseok or st patrick's event, im assuming. any plans were obvious once the event got underway.
the best is to be honest, but u dont hv to explain if u dont want to. but dont mislead, n others will take u at face value n trade accordingly. at least, i hope tats wat i did during chuseok, st patrick's n other limited events.