I was experimenting with HIs this morning. It took me no more than about 2 minutes every time, and I managed to have about 10 within the hour. Seems to be way more effective when you aren’t thinking about a certain topic and just let your mind go wild with randomness like it usually does when you’re about to fall asleep. As soon as the HI starts and you realize it, I found it easy to change the atmosphere right then and there, instead of trying to achieve it straight off whilst trying to get to sleep.