All you need is a plain button down shirt, a printed button down shirt (a cool printed piece of fabric will work as well), scissors, ruler, pins, and a sewing machine or the tools to sew by hand.
Step 1: Prepare the Ruffles
Cut out six 1 1/2 to 2 inch strips of your printed shirt. Finish your strips either with a serger or a zig zag stitch.
Step 2: Sew the Ruffles to the Shirt
From the collar down, start attaching your fabric strips. To get the ruffle, just scrunch the fabric strips up under the foot of your sewing machine as you go, and attach down the length of your shirt.
You have a ruffley, victorian-y, Sweeney-Toddy inspired shirt!