Here is how it works. You choose something that you would like to work on and do it for 21 days. (to make it a habit) Such as drink 80oz. of water
, walk a mile,
or what ever else may come to mind. 
You do a count down. But if you miss a day...you start over to day one. 
And you can start over many times, but if you're constantly starting over.....well then....I would say maybe you should find something else to work on for 21 days.Also, during the days you're sick and your body just doesn't feel good,
we have what we call a "pause". You pause your efforts until you're feeling better and just continue from what day you stopped.Simple you say.....believe me,,,,it's not as simple as it sounds...there have been times that I just had to start over.
And just a reminder, this is not a competition against others. We are not competing, we are trying to make better habits in our lifestyles and this is just one way to help kick start it.
So anyone like to join???
I know how busy you are and I came here tonight to specifically find the old thread and start a new one for you/us. But ya beat me to it! 
I actually started today but won't start counting until tomorrow because my challenge is more than one thing, sort of. It's basically getting back on track with drinking my four bottles of water every day (on number three right now & I won't get a #4 this close to bed, thus the reason to start counting tomorrow), take my vitamins and get that exercise in. The exercise...while I plan on working up to 3-4 miles a day, my challenge will just be to get in no less than a mile. So here's to tomorrow ladies 
)