Good question. Generally, for the overall challenge, you will be logging your weight and following your own diet plan. The teams are broken into colors and your team lead will want to set up a separate group forum for you and your team to chat. Typically this is where you would want to have individual mini-team challenges for the group. For example, on the last challenge I facilitated, I was on the Green Team. Our leader would either post a mini-challenge for the week or a team member would come up with one for everyone to follow. Things like getting all your water in a day, taking at least 10.000 steps or logging all your meals. The sky is the limit when it comes to what you and your individual team decide to do for mini-challenges.

Let me know if this helps.