Here is what worked for me while on holidays.
(1) Early morning jog, this can be a walk. It was cooler first thing in the morning. Then go and enjoy and health protein breakfast, like an omelette.
(2) Drink plenty of water everyday. I suggest more than two litres. Add another litre onto that but sip the water throughout the day, every 15 mins or so.
(3) When you hit the fast food chains, look at the salad menu. There could be a nice chicken salad waiting for you along with your water or an americano.
(4) Use an app to monitor your daily steps each day. Try and beat it the next day.
(5) Lots of sex! It much more interesting than running on a treadmill, but do put the effort in.