About T-Shirt Design
If you like shirts that actually have some personality, Not Today Satan T-Shirt is a good example. Anyone who is into everyday humor will probably understand the idea right away.
This would be easy to give as a gift for casual days, birthdays, or any random day when you want to make someone laugh. It has the relaxed feel people usually want from novelty shirts without getting too complicated. It feels casual enough for normal days but still has enough personality to get noticed.