Good day, please anyone with ideal on how i would be make this work easily, a friend of mine who ownes a blog, seffixyworld..com has decided to buy a hosting and a domain in order to switch from his free to his own domain, and he doesn't want to loss any content in his blog, in terms of news and updates, so please i will need someone to put me through, is it possible to change the seffixyworld..com to seffixyworld.com so that its content will still remain untouch and he can continue from were he stops, I have already gotting the hosting and domain for him, but how to fix the blog is the problem now, please i need a God sent to help me with any ideal.

It's quite simple.
You can go through this: http://www.techydoor.com/how-to-add-custom-domain-to-blogger-com/

Take care.