Once I was ready to start making his costume I fitted the fabric directly on him.  Other than adjusting the width no other cuts were needed.  I had excess fabric on one side and marked it with a pin and made the cut.

This is another view to give you an idea of the spacing for the arm.

I removed the fabric from my little model and got ready to sew.

I used a zig-zag stitch because of the stretch of the fabric to stitch the top of the fabric.

I added about a .5 inch area of stitching for the bottom of the armhole.

Once everything was stitch I used art paper (torn from a big roll from Ikea) to get an idea of spacing and lettering and then I used a sharpie to write Reese's.  If you're really into things being exact you can take an empty wrapper to an office supply store or other such business and have them copy and enlarge the lettering to the size that will fit your costume and then use that as your template.  I wanted this to be as stress-free as possible so I just hand-lettered mine.  Once it was done I cut out the letters and then traced them on my yellow fabric with a Sharpie, cut out the letters and used fabric glue to glue in place.  

I also cut out freehand the peanut butter cup in the top right corner of the outfit added the filling and cut out the peanut butter cup for the bottom beneath the Reese's lettering.  Glue all of those items and the calorie information onto your costume. 

For the next step, I used black paint in a tube with a fine tip and yellow paint in a tube with a fine point to add the details.  Don't worry about it being exact....just have fun!

Be as detailed as you want to be but if you are pressed for time leave out the little stuff!

I also outlined the yellow lettering and I was good to go! That's it....my stress-free Reese's Peanut Cup Halloween Costume.  If you make one or something similar I would LOVE to see it!