A simple grammar/punctuation request

Can I ask one thing?

I try to be relaxed about proofreader things when I'm reading blogs. None of the ones I read are awful about such things, but everyone makes mistakes sometimes, me included, and I roll past it without too much pain. But would you mind one little piece of advice?

Use it's for it is or it has.

Otherwise, use its with no apostrophe.

It's so simple.

Thank you for listening.