How does one blog?

I honestly have no idea how to do this, but I’m going to try out this whole blogging thing (:  I think I’m going to be posting giveaways I’m entering, my photography (critiques are welcome!! :P), and I’m not sure what else yet.  So yeah, please, if you have any pointers, tips, tricks, help of any kind, I would LOVE to hear!!  Thank you all!