Hi there,
The easiest way, with one microphone, is always just to make the sound you want to record, and record it.
I know that sounds silly or stating the obvious but it's true.
Get the guitar and your voice to be well balanced in the room, and use the microphone a good few feet back to capture that, as someone standing there would hear it.
If you want to get a little fancier you could find out if the camera input is stereo and, if it is, you could McGuyver a way to record guitar on the left (direct) and voice on the right then mix later,
but you said you don't fancy using software so, yeah...
Mic a reasonable distance away; Sound good.
Easy.
If you have a say in the environment, that can help a lot. Try to choose a room that's well furnished or has a lot of dense material in it.
A living room a carpet, a full bookshelf and settees is most likely better than a tiled kitchen, for example.