Find a rift in the Hotel and tap on it, then tap the warper icon that appears above the rift. This triggers a party invite that will appear over your head, and start counting down (This appears as a blue ring around a circle). If there are friends in the vicinity, they can join the party!
By watching two in-game ads a day during extraction of currency from the rifts, you receive 15 minutes worth of currency instantly. Please bear in mind that you can only watch a limited number of these ads every day. You can also call your warper back from the rift when you feel like you’ve extracted enough currency.
After you’ve called your warper back, or you’ve finished using the rift, you can watch another in-game ad to double the amount you just extracted.