Making a plan to have wonderful day is not something that can be easily done. In fact, if you are the de facto leader of a group and you have been tasked to make some plans for your group, you might soon discover that it is not a good idea at all.
You will only be good at this if you love to take care of things pertaining to certain events. But if you find yourself enjoying a party instead of managing it, then you should not try planning one at all. You might just mess things up. Leave it to the rest of the group and just enjoy whatever happens.