Starting with your shirt, I flip mine inside out and iron on Floriani no show fusible mesh in a square that is a little larger than the design that you are planning to applique.
http://www.rnkdistributing.com/product-info-floriani.php?No-Show-Nylon-Mesh-Fusible_-pid65.html
There is a fusible side and a non-fusible side so be sure that the fusible (glue) side is facing the shirt and the non-fusible side is facing up. You want the stabilizer to fuse (stick) to the shirt and not to your iron.
With the iron on medium heat completely adhere the fusible mesh to the shirt by ironing thoroughly. If your iron is too hot this product will melt so you can go up to medium/high but stay away from the highest heat setting unless you enjoy cleaning gunk off your iron. Stabilizer should be smooth and adhere completely.
Flip your shirt right side out and fold in half and mark the center with a pin.
Unfold shirt and then get your fast frame ready. I am using Floriani Perfect Stick sticky stabilizer on the fast frames. This is the only brand that I have found that does not gum up my needles. It has silicone embedded in it which keeps the needles clean while sewing.
http://www.rnkdistributing.com/product-info-floriani.php?FlorianiPerfectStick-pid57.html
Flip your fast frame so that the back (under side) is up. You can tell it is the back because if you look at the top of it (shown on the right side of the picture) there is an indentation like a L running across the top.
This is the side that you are going to attach your perfect stick to. Cut a piece of the perfect stick the size of the frame. Unpeel from the paper backing and attach with sticky side down. If any overlaps bring it around to the front. Make sure it is tightly adhered and not wrinkled.
This is looking at the backside of the frame with the backside of the stabilizer adhered.
this is the front side of the fast frame with the sticky side up.
Slide your frame inside your shirt. Try to line up your center pin with the center notch at the top of your frame. I then measure from the shoulders to the top of the frame on each side to align the frame and make sure it is level and centered. Smooth your shirt across the sticky stabilizer with your hand so that there are no wrinkles. The picture above has not been smoothed yet because I was still aligning the frame.
Now that it is smoothed out, mark your design center with a water soluble pen. Measure the finished size of your design from the center mark to all sides to make sure that you are within your frame for the entire design. Make adjustments as needed so that your needle doesn't come close to the frame when sewing.
Remove your pin. You are ready to attach your frame and shirt to your machine.
Attach your frame. Notice that the frame top is notched so that it fits flush with the bar. If it is not doing this than you probably have it wrong side up. The frame should be tightly secured with the center screw and should be looped over the two side holes (the really shiny circle in the center of the photo is the right side hole).
Make sure the top of the shirt is tucked out of the way so that it does not get accidentally sewn into the design. Oops...hate when that happens.
Align your design with your center mark and test.
Sew your placement line for your first applique fabric. Stabilize the back of your first applique fabric with either another piece of no show fusible mesh or the stabilizer of your choice. I used heat and bond for this but usually use the no show mesh.
Place fabric over your design lines and sew your tack down stiches. Remove frame from machine and trim your design with a good pair of applique scissors. Note..you are not removing the shirt from the frame.
Put frame back on and sew additional fabrics as the design calls for using the same method.
Remove frame when design is finished sewing. All should still be smooth. You can now remove the shirt from the frame.
Flip shirt inside out and pull up the excess stabilizer from around the design and trim.
Flip shirt back and iron front side completely. You are finished!