just visit blogger.com and login to your google account.
Follow simple instructions that let you create your blog address, title and small profile block.
If your brain is full of ideas that flow very often and you have a weak memory then I recommend to use blogger app from playstore.
Note: you can aslo create a blog post without loggin in to google. You can actually do it just by sending the blog text to asecret email id chosen prior by you, which you can find in blogger settings.