In the measure you wish to change key signatures press F5 and in the key change window select the key you want. The song will stay in the new key until you change it back, thus you will have to do this in every F to D and D to F measure you wish to change.

I hope this helps.

Whenever I get something stuck in the back of my throat, I dislodge it by drinking a beer.
It's called the Heineken Maneuver.

64 bit Win 10 Pro, the latest BiaB/RB, Roland Octa-Capture audio interface, a ton of software/hardware