"You'll need to hold it. But with practice, it won't be an inconvenience to you. It's like.. partially listening to music in the background while your focus is on something else. You know it's there, you can hear it. And even though your brain is concentrating on other things, as long as you occasionally remember the spell is still happening, you should be fine. And if you forget to maintain it, the spell normally takes a long time to dissipate. It won't vanish all at once and leave you out in the cold, so to speak."
Good thing for that, too, because Strange certainly hadn't stuck around for long after that New Year's party to ensure everyone remained comfortable.
Another smile tugged at his lips. He could see that Daphne was frustrated. It reminded him of himself when he had been wrestling with learning certain spells. Strange himself was awfully impatient. He wanted to learn things now and hated the idea of spending endless hours practicing. He still hadn't fully overcome that need for immediate results, so he entirely understood how Daphne was feeling.
"It's okay. It's not an easy spell, don't get discouraged," he spoke, giving her a nod, "It gets easier, I promise. Go on, try one more time."