First and foremost, be sure you have enough time between #flights. A plane being delayed happens frequently, and if you have to take more than one plane to reach your desired destination make sure you have a window of an hour and a half just in case. Also bear in mind different time zones!
Do you need a passport? If you do, make sure you have enough time to get one or to renew it as an urgent passport request isn't cheap. Never forget to check that the passport validity and blank pages rule apply in the country you wish to visit.
The hotel location is the golden key to a pleasant trip so you shouldn't underestimate the distance between your hotel and the centre of the city. Yes, these type of #hotels may be more expensive than others located in the middle of nowhere but unless you wish to sleep most of the time and only visit a couple of tourist #attractions, then you have to take into consideration the valuable time and money spent inside of a bus or a taxi that could be better spent somewhere else (near a pool or a drink?!).
If you feel something is too good to be true, you are probably right. There are many misleading #promotions out there, thus you must always check that the services you think are included are indeed included and what the additional cost is if they aren't.
Do plan your #holidays beforehand then have fun with the 'few' adjustments you make when there. Trying to do everything you can think of means that most of the time you won't be relaxed enough to properly enjoy it. #Cities like #Paris, #Rome or #Lisbon deserve a visit of at least three days! However, even at the end of a whole week away you may feel that you needed more time. Don't worry, as these cities will still be there next year. There is definitely nothing wrong in repeating destinations and exploring them with an added confidence.
Use the experiences of others to improve your own. Check blogs and YouTube opinions about where you want to go, as they can add useful information about the main tourist #attractions and treasures only known by locals.
Enjoy the summer!