A Simple Way to Remember

Many people these days seem to often mix up "its" possessive, with "it's" the contraction. To correct this problem, I've come up with a simple phrase to help people remember the right way of doing things:

“‘It is’ is ‘it’s’ or it’s ‘‘tis,’ not ‘its’; ‘its ‘it’s,’’ ‘tis ‘its,’ it's not ‘it’s.’”

Actually there really is a way to remember. "It's" is the contraction, where the apostrophe replaces the "i" in "is," whereas "its" is possessive. You wouldn't put an apostrophe in "his book," or "her book" (for hi's or he'r both look dumb,) so why would you put one in "its book?" 

I still like my sentence though. It's great.