Even though a Happy New Year Speech seems to be obvious about the Happy New Year message, you do need to prepare for such a speech. Will you reflect on the past or more focus on the future year / years? Will the speech be funny or serious or a combination?
Are you planning to make the speech very personal or more general? Is there an underlying message? Will you use story telling techniques? Is there a specific action item that you want to bring across during your speech? Do you plan to have interactive elements in your speech?
Even a Happy New Year Speech will require preparation to make it more impactful and memorable. You can take advantage of the supplement that is part of the book Public Speaking Excellence that includes more tips about giving a great speech.