Put it at the very start of an edit as the opening greeting, before the main scene or reaction begins. Follow it with Anime Ahh for a surprised reply, then let the scene play out without adding another greeting sound.
关于此声音
The Hayasaka Hey Hey clip is a short 2.8-second vocal sound built around the repeated greeting hey hey. The brief repetition gives it a light, attention-getting feel, like a quick hello meant to catch someone before a conversation starts. It works best as a small, cheerful interruption rather than a long line.