From the Introduction:
Not everyone has dice readily available (especially polyhedral dice!), and so Holiday Heroes has been designed to be run with something that nearly every home, bar, pub, or holiday destination has available: a ordinary deck of shuffled playing cards with two jokers. Place this in the centre of the table.
You will also need the obligatory pen and paper (or napkin!) to quickly create characters on and keep track of wounds. However, even these simple items are not readily available. Consider using your mobile phone's text messaging feature, or a suitable app, to make notes.
Optionally, you can print and cut out the bridge card-sized rules summary and character cards found at the back of this book, so you can have the game with you wherever you go. You could even slide these into someone else's deck for them to (re)discover later!