Change post url

I have a Web page that has a blog. It has a static home page, and you can access the menu using the top menu.

When I visit my site, it looks like:

www.mysite.com

When I go to my blog, it looks like:

www.mysite.com/blog

But when I visit a post, it looks like:

http://ift.tt/1XwWb27

And I want it to look:

http://ift.tt/1PSvuCT

How can I achieve this? Is there any way without plugins? Or maybe, any plugin that won't crash anything?

Thank you!

via Chebli Mohamed