It's really easy, but for that u need to read other people's blog, while reading you need to visualise your trip and try to put it in your words.
don't worry about English n grammar, your experience will teach it to you.
main and important thing is to start blogging
Just start writing where ever you can and if possible try to make a new website for yourself to boost up your confidence. It could be a free one year trial website too.
Share your real travel experience in your words and with all required details so that your story and experience can inspire others to travel a lot.😀