First, cut the freezer paper. Unless you are hand drawing the design, it has to fit in your printer. Use a piece of printer paper as a guide, the ruler as a straight edge, and the exacto knife to trim the butcher paper. Print the graphic. The freezer paper has a shinny side and a papery side. Print on the papery side. The design I'm using as an example is is from a local band, Killola. Their blog
has a DIY t-shirt thing too. The print should be black and white with distict edges (monochrome).