This will be helpful for you @ronit_masih, kindly follow:
You can pitch like this for guest blogging…
“My name is XYZ, I’m a regular guest blogger, I have written a wonderful article about ‘so-and-so’ and I would like to publish it on your blog with my author bio.”
Or you can be creative and do something like this:
“My name is XYZ, I’m a regular guest blogger on popular brands like Mashable, TechCrunch, etc., and I would like to publish an article about ‘so-and-so’ on your blog as well. Do let me know after publishing the article on your blog, I might use this as a reference link on my future guest articles on other popular blogs.”
Do experiment with your email pitch, you can try to ping them on Facebook and Twitter as well. Best wishes.