Every time you mail a letter you could be building opposition to the Trump regime.
I created this page of labels that you can print out and attach to the left side of every letter you mail.
I circle mine with a bold red marking pen.
They are formatted for a very common kind of address labels: 30 per sheet with 3 columns of 10 labels each, with dimensions 1″ by 2 5/8″
http://parallaxperspectives.org/print-these-anti-trump-labels-attach-them-to-envelopes-you-mail