This is simple and quick. No longer am I the one who passes up a free t-shirt. Hopefully they'll be many more t-shirt recons to come.
Step 1: First thing look up Matsuzaka, his name is on the back of this shirt. Lay the shirt flat and iron make sure not to go over the lettering. Then turn it inside out.
Step 2: Take a shirt that fits you well, lay it over top being sure to have the shoulders line up. Pin the outline of your well fitting shirt through both layers of the t-shirt. Congratulations you just used a pattern. It was my first time too, quite enjoyable. Sew up both sides with a machine.DO NOT stitch the arm holes shut.
Step 3: Cut off the excess and the sleeves. Make the new sleeves by cutting a square from the original sleeves. You can pin them to ensure the sides will be equal. For reference the sleeves will be on your arm the same as before just much smaller therefore the original hem will need to be maintained.
Step 4: Double thread a needle with a contrasting color.. The thread should measure approx 7-9 inches put a gathering stitch through the un hemmed end. You can fold and iron the gathered section to make sewing on the machine less stressful. Run a machine stitch on the inside of the gathering thread, now remove the contrasting thread. Repeat for each sleeve. Try try try as hard as you can to have both sleeves be exactly the same.
Step 5: With t-shirt still inside out fold back the arm holes and pin the sleeves into place remembering sleeves should be inside out as well. The most important thing is to have the sleeves lined up evenly on each arm hole. Measure and mark the center of the gathered edge, pin it to the shoulder seam of shirt, then continue pinning around the arm hole. It should not make it all the way around to the armpit. At this point flip it all right side out to check for huge differences between the two sides. Flip inside out again and carry to the machine. Stitch around the pins and voila! capped sleeves. Bravo! (I always have to go back and make little corrections to the sleeves, it's no big deal keep working with it.)
Here it is, the finished product. Now I might wear this thing and it was free. This is the 3rd and best t-shirt I've reconstructed, each time it gets easier.