The "Wintersown Method" basically means to plant the seeds mid-winter, in a shady spot, and cover them with something like a soda bottle with the top left off, and the bottom cut off. The plants germinate when the season is right for them to germinate.
The main problem that I have seen people having with growing pollinated potato seeds, is that they keep them too warm. Therefore they germinate poorly. Then they don't get enough light while being too warm, so they get long and leggy. The wintersown method avoids both of those problems.