grab a big t-shirt and a buttondown shirt. it would be swell if you have a tank top for tracing.
instead of the buttondown shirt, you could also use fabric or another t-shirt for the yoke.
lay the tank top on the t-shirt, and mark like so.
cut where you've marked, but only cut the scoopneck out of the front.
so the back piece should look like this ------->
sew the front and back pieces together.
feeling a little lost? check out the sewing basics or post a question in the forum.
save that piece that was cut out to make the scoopneck. that will serve as a pattern for the yoke.
lay the t-shirt yoke pattern on top of the collar of the buttondown shirt. cut around it as shown.
now you can match up the buttondown yoke with the scoopneck of the t-shirt and sew them together.
using what's left of the buttondown shirt, you can add ruffles, sleeves, etc. to finish it off.
fonte :
http://www.whatthecraft.com/pics/tut/yoke/yoke6.gif