I used it about a year and a half ago, but i think the process could still be the same. With the game closed, you have to place the female cards, into the male "chara" folder. Then open the game, and edit a male character. You should then be able to load the look of the female card onto the male body by going to the last tab where you can save/load looks. You then have to resize the chest and add a dick.
There is another method, but it stopped working for me when i updated the game, but it could just be a problem that i had alone. If you go to edit a male again, you should be able to drag and drop cards, and it will automatically load the character. You still have to edit breast and add a dick though.
Do the reverse for the males. So you would be able to load male as female, and female as male. You would have to edit the voices though.
