Best Practice for SharePoint 2013 Features

I am migrating SP2010 to SP2013 in this year..

My current SP 2010 is lot of mess.. lot of sub sites and users groups in each sub sites.. no control on document management.. no branding etc. etc.

In the SP 2013 , What all feature or Key Point I need to consider while designing the SP2013.. Any Step by Step instruction will be very helpful for me to design this new SP 2013 installation..

Thanks,

Anurag