I think different people do it different ways, but most post anew with updates although, I sometimes cut and paste a portion to make it easier to keep track of my progress. I think you will find, most challenges are pretty relaxed, whatever works for you is great! Welcome!
Posting anew is more likely to put you in the flow of the conversation, however. People are less likely to notice if you're updating your first post. I generally keep my log on my computer, then cut and paste into 3FC.
Question about joining challenges
