Calmly and steadily record your voicemail. Don’t rush it to the point where the customer can’t decipher everything you’ve requested on the message. To ease the process, write your voicemail down with pause points. This will ensure you annunciate everything clearly and can assist in managing your speed.
First of all, I want to say great work on using the phrasal verb “to pick up!” Native English speakers love phrasal verbs and we use them often. In this example, to pick up the phone means to answer the phone.

Think through what you are going to say before you place the call. When men hear the beep, they often freeze up and forget what they wanted to say. If you want to be the go-to guy at work, then you have to exhibit competence on all levels. Don’t spoil your confident image by hemming and hawing and filling your messages with “uhhhhs,” and “ummmms.” If it’s a really important call, consider writing out what you want to say beforehand. If the person picks up, great, you now have some notes to remember what you wanted to talk about. If they don’t answer, you can leave a clear and concise message.
Hi! I seem to be in the room, but I can’t quite locate my phone at the moment. If you leave a message and number, I’ll ring you up whenever I find it, or if you happen to know where I left it, let me know!