How to make your own sequined Tee:
Mark a pattern. The sequins I used where the same size as the squares on the graphing paper I used, so it worked out well. Feel free to copy mine :)
Stick your paper over the area where you want your sequin pic. Put something inside your Tee, for example a book, to protect the other side from the next step.
Take a pencil and press it through the paper, making marks on the Tee to see where to attach the sequins. Remove the paper.
I used sequins and sewed them on, but you can use for example iron on studs instead. It'll probably be much quicker, but I haven't used any yet.
I used silver sequins for most of the owl, but put gold ones as eyebrows, eyes and beak.