Had you told me when I was a teenager that I would someday crochet a tissue box cover, I probably wouldn't have believed you... or I'd have been mortified at my (imagined) future state of mind. (g) Yet there it is. I have made one of those "little old lady" tissue box cozies.
I saw the pattern on a blog or two-- then my husband caught a cold, and our unadorned tissues came under my eye. Well, it was inevitable, really, that I should take a break from my current pet project (the Circle of Friends afghan) to make a tissue cover. It's a simple and very quick project. An experienced, speedy crocheter could whip it up in an afternoon. The rest of us might stretch it out over a day or two of easy, pleasant crocheting.
Mine's not the prettiest I've seen. I really prefer the ones in rainbow colors... but since this one will probably be living in our bedroom, I decided to go with the colors that tend to harmonize best with our bedclothes-- green, blue, yellow, and white. (And I just happened to have those colors of yarn in my stash, un-spoken-for by any contemplated projects.)
If you happen not to have seen the pattern before, it's the Granny Tissue Box Cover, by Michelle Kludas.
The pattern's written in English crochet terminology, but it's easy to translate into American abbreviations. If you can remember that UK terms state things one step larger than US terms do, you'll be fine. (So an English dc is an American sc, their tr is our dc, and their d tr is just a plain American tr. Chains and slip stitches are the same in either system.)