Do Research
Don’t just jump into it without doing your research first. There are a lot of things you will need to learn before you start your blog. So try and contact other bloggers, maybe try and find people in Facebook groups who blog, or even a friend/family member and ask for their help to get you started, ask them for tips, etc. Kind of like a mentor thing, this will help you out a lot and keep you from getting discouraged from pursuing your dream of becoming a blogger.