How do i use "AlignOrientation" correctly for viewmodels?

I saw in my freinds fps game that he used the "AlignOrientation" thingy to make his viewmodel shaky when moving. And i don't know what a "AlignOrientation" and how to use it. I used "CFraming Lerping" for my viewmodels. Can someone please tell me how to use this wierd thing for viewmodels correctly?

Thanks.