How do I rename my thread?

[r1nzl3r]

I'm deeply sorry if this was asked already, but I've forgot to add a size of file I'm sharing to the thread's name and it bugs me. Is there a way to rename a thread?

 

[CoolKevin]

yes by letting me know

if it is only file size add it to the post where it belongs, there is no point in putting it on the title bar as sizes can change