One of my favorite things about sending letters is decorating the envelope. The envelope is a blank canvas, and it looks all too dull with nothing but the addresses and a stamp on it.
Even if you don't consider yourself the most creative person, give it a try. Send a letter to your parents, sibling(s), or friends and take the time to decorate the envelope. It makes it more festive and would brighten the day of anyone who receives it.
There is a page on pinterest about decorated envelopes. If you're looking for some ideas or would like to just check some out, you should definitely take a look at this website.