For newbies, we do a group fast at the start of each month. It's not a big thing, it's just discussion for those that like the idea of a monthly extended fast, where we can share our experiences in a single discussion. The focus date for the fasts is the first Sunday of the month, with everyone starting on the day of the week that works for them around that date. Most people start after the last meal on Friday or Sunday, but other options are great, too.
When do we want to do the December fast? By our founding principles, if should be the 6th and 7th of December, but my instinct says next weekend - 28th,29th would be for me. Happy to support either (or both) dates, but if you are planning a monthly fast which weekend suits better.
NB: January should be fine, fasting around the 3rd and 4th. Excellent dates to start, and close enough to the 1st for those that want to start at dawn of a new year - at the dawn of a better year, I hope!