I have to begin by admitting that, yes, I do sometimes fold down the page corner to mark my spot. This is obviously not a very nice thing to do to a poor helpless book, especially a hardcover library book with the thick paper that will hold onto the memory of that crease forever.
My other less than perfect methods of not losing my place in a book have included: placing a tissue I have on hand between the pages (and with my all-seasonal allergies I always have a tissue on hand), leaving the book open face-down on some flat surface which in it's own way is as cruel a thing to do to the spine as turning down a page is to the paper.
However, before the book lovers of the world gather an angry mob with fiery torches to punish me for the error of my ways - let me be clear that I prefer to use a bookmark of some sort and have done so for my entire reading life.
The Erie County library system that provided 99% of the books that I read up until I moved to California had these cards in the backs of all the books that they would stamp with the return date. Ah, stamping a return date - already it sounds like such an antiquated notion. However, these cards were great. On one side they had the numbers 1 and 2 and on the other side 3 and 4. Using these cards I was able to devise a system wherein if I left off on the left hand page I would place the card so that the 1/3 was sticking up, and if I was on the right hand page, the the 2/4 would be up.
It was a wonderful system also because in essence every book came with it's own bookmark, but also a little pocket at the back of the book to keep the bookmark in while I was reading so it didn't get lost in the couch cushions, bedsheets, pool water, or wherever else I happened to be that day.
Since then I have struggled to find another system that works as well. Sometimes I'll use the little printout receipt that the library gives me when I check books out. Sometimes I'll use some odd scrap of paper that happens to be lying around. And sometimes I'll find a misplaced bookmark and actually remember to use that.
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And as luck would have it, I also received an excellent book mark from one of my crit partners during our Secret Santa this past year. As you can see, it is currently marking a page of a reference book (also part of the same SS gift) on my cluttered bookshelf.
What about you? Tell me in the comments if you're a book marker, page folder, or have some other odd method for marking your page?