Boy, you can't go wrong if you follow Joanne's excellent instructions!
Just a small addition: Make sure that your milk jug or other container lets some light through. Around here our less-expensive supermarket milk is the Hoods brand, the jugs of which are totally white and definitely too opaque. Joanne's milk jugs in her photos are the right type. You should be able to see the shadow of your finger inside when light shines through. For my Hoods jugs, I cut out the sides and just place a clear plastic gallon-sized zip-lock baggie (vented) over the top but it's much more cutting to do and a pain.
Also, if you wish to reuse your milk jugs for next year's wintersowing, rather than writing on them you can place a plastic plant marker inside with all the plant particulars written on it. But I generally just start over each year because I end up with so many recycled milk jugs!
