There are so many tutorials "how to setup vpn tunnel". Unfortunately most of them are pretty much manual or are based on some bash magic.
I found myself repetitively doing the same thing over and over again... This article will show you how to setup full vpn tunnel (with sniproxy and dns server) with as little as one click (once you have keys) with vagrant and CoreOS.
As bonus point I'll briefly describe how to setup your openwrt to transparently pass traffic through tunnel.