So what does thick, white, non-stretchy mucus mean - is this leading up to ovulation or already past it & now leading up to a preiod?
That's non fertile mucus - usually the type you'd see after ovulation or very early in a new cycle.

I really recommend the book "Taking Charge of your Fertility" by Toni Welscher - it's my charting bible. I've charted for 15 years on and off and this book has been there through it all It has heaps of info and also lots of sample charts that are really good for reference and learning.

Also check out Ovulation Calendar and Ovulation Chart - FertilityFriend.com - they have charting "tutorials" that are great and you can also record your chart online so their software can help you interpret it.

Good luck!