I tried several times to add a second layer to a piano part, using the on-line instructions. So confusing and made a mess of the score, adding ties, etc…
Then I remembered how easy it is in Sibelius: Click a number at the bottom of the notepad and you’re done. So … I downloaded the free version. Missing a few features, but enough to allow me to finish the project.
Did you try hitting shift-V when you’re in note input? Shift-V adds a new voice, and afterwards, V will shift from voice to voice when you’re inputting. The cursor will show a plus sign, with a downward stem, to show that you’ve created a new voice.
So, during note input you can press Shift+V to create a new voice the next voice after the default Up-stem Voice 1 will be Down-stem Voice 1. This will be a note pointing down with a + sign.
If you click the button on the left zone, it will activate the next voice available. E.G. if you only have one voice (Up-stem Voice 1) it will create the next possible voice (Down-stem Voice 1).
The next step is to input a note – similar to how in note input “normally”, the caret appears, but no notes go onto the staff until you press e.g. G for a note whose pitch is G.