I walk a lot usually, so I would say getting used to it. It helped that I like walking anyway. Public transport should be easy to get in the places you're heading to, but if you want to walk, map out the shortest or scenic route in advance so you don't feel like you're walking in circles.

Good broken-in shoes and insoles, definitely. They make you feel less cranky. Also to reduce crankiness: a bottle of water and some snacks in your bag. Even with cafes around.