I knew about the tunnels when I worked at DL, so I actually never needed directions. But the T4-T5 tunnel is new (to the public anyway), and after I did a dry run last summer to get an idea of how to explain to my mother, I thought better to take her through it myself.

IMO, it's confusing and counterintuitive to walk the bridge from T7 to T6, which is located near landside, and instead of going straight towards T5, you have to go into the middle of T6 in order to get to the tunnel. And underneath T5, if you are not careful enough, turn the wrong way and you'd end up outside in baggage claim.