What you'll need: Cutting board, ruler, scissors, x-acto knife, fabric safe acrylic paint, book/magazine, plain tee, and double sided adhesive paper. 
Begin by creating a design that you would like to use as your template. Then print your image onto the adhesive paper. Using an x-acto  knife begin to cut out the image (you can also use scissors). 
Place either a magazine or book in between the shirt to prevent the sides from sticking from each other.  Peel the backing off of the paper and position it onto the shirt. Next you would want to use the ruler to flatten the adhesive paper down to prevent any bubbling.
Depending on the thickness of the shirt you will want to do multiple layers. Make sure to let the paint try between each layer. *Since the lettering was difficult to cut out by hand I used a Cricut Expression cutting machine to do the font. Stencils will work too.
Finally, slowly peel the paper off to reveal your design. The edges of the shirt should come out clean without any feathering or bubbles from the paint. Have fun!!!!