How to make a BillboardGui ImageButton Open a ScreenGui's Frame?

The script I tried:

function Clicked()
    script.Parent.Visible = false
    script.Parent.Parent.speechframe.Visible = true -- speechframe is the frame (the one in the screengui's) name.
end

script.Parent.TextButton.MouseButton1Click:connect(Clicked)

A serverscript wouldn't know which player clicked on the button. Here's a solution:

Put the BillboardGui inside of StarterGui (or playergui if you parent it later), and set the adornee (property) to the part you want it displayed on. You can then use a localscript to handle the click events.