The way to sign "shirt" is by grabbing your shirt in the upper chest area - in the middle or slightly to the right - between your index finger and thumb. Then tug outward a few times. The sign for shirt can be done with one hand or two. If you do it with one hand though it might sometimes be misunderstood to mean "volunteer."
SHIRT / volunteer / apply
Remember: This is also the sign for "volunteer, apply, pick me, candidate" and related signs.
If you need to distinguish between the sign for volunteer and shirt, I
recommend signing "shirt" with two hands.
Related sign: "BLOUSE"
All material copyright © 1996 by Dr. William Vicars