yes, to echo the others above -- FRA can be confusing because every terminal looks the same, and I at least can never tell where I am just from looking at the surroundings.

The main thing to remember is that when you arrive in FRA you will have to pass through passport control, even though you stay in the airside of the airport, so factor in an extra 5 or so minutes for that line.

The other thing is, if your gate requires you to change terminals, and you find yourself at some point with the option to take the staircase or elevator, DON'T TAKE THE STAIRS! They go on forever -- like 8 levels before you reach the bottom! It's the most deceiving staircase I've ever seen, for being a major exit point to another terminal, the door looks like a janitor's closet. I thought, oh, this must be some door to a shuttle bus, since it looks like that. No, it's like if they had a single door, to the ORD midfield concourse underground walkway. Save yourself annoyance and wait for the elevator...

Otherwise, it is straightforward at least, just follow the signs. And enjoy the Sen lounge.