I'm a bit anal with most things and like playing with pcs so I use Microsoft One Note although Excel is just as good but not as pretty (for me). So my planning:
1. A page of the different fabrics I have with copied and pasted notes from where I bought on washing etc and how much there is and tag boxes when used
2. A page showing what I intend to do in the year and with what fabric (that can be a bit laughable looking at it at the end of the year) with tag boxes to clear when done
I've been doing this for a few years now because I was buying fabric when I fancied it or it was cheap and then forgetting I had it. When I finally had a sort out and re-arrange, the 20 meters I thought I had was nearer 30 and I suspect there is a bit more unaccounted for.
I'm definitely not Darkside, I want it on my back and on my back only, so their planning will be substantially different from mine.
I'm not really into embroidery either although I've seen some fabulous stuff on this site.