Have you checked out LOL Shirts  yet?
I have bought several presents for friends over the last year from this site and they are ALWAYS a hit.
Through 11/28 ALL the shirts on the site are $8 and shipping is FREE.
If you don’t understand them, ask a friend who has a “nerd board” on Pinterest (you can check out my nerd board ) and they can explain them.
Then buy them a shirt from LOL Shirts  as a thank you.