If you want to write a post and become an author on Mystery Techs Then fill the form and get email by me which type of email you get, if email is send to you then click Accept invitation then choose your gmail account and you went to the blogger and now you can create a new post.
Example:-
Hello,
The Blogger Team
The purpose of this message is to inform you that Mystery Techs has invited you to contribute to their blog "Mystery Techs". To accept this invitation, click on the button below.
Accept invitation
Important: You will need to sign-in with a Google Account to accept the invitation and start contributing to this blog. If you don’t have a Google Account you can create one here.
Happy blogging,The Blogger Team
:-s