Create layouts with multiple cameras, screen captures and images?

You can create pretty sophisticated Scenes in OBS, here’s a few tips and examples.

Let’s start by adding a background image to our scene : add an image source in OBS and choose your background image file.
Then let’s add a Window Capture of our DAW, here it’s Ableton Live.

Choose the window you want to display in OBS.

If the window is too large or small, you can automatically adjust it to the OBS frame by going to control-click or right-click > Transform > Fit To Screen.

Adjust the size of the window by dragging the red frame and place in the OBS frame.
Now we can add a webcam.

You may need to change the order of layers to bring one source in the front. Here, let’s bring the webcam frame to the front as it is hidden by the Live window. To do so control click or right click > order > move to top.

If you need to crop the frame of one of the sources/layers, hold option (⌥) while moving the border of the image (that will turn green).
You can also add more still images, logos, a video loop or a video transition to add between your scenes or as an intro to your session, a web browser window etc.

How to invite a guest on your live session?

<aside> ⚠️ To invite a remote guest on a live session you need to make sure you have a good internet connection through ethernet.

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Set up a video call with your guest using any video chat solution you like (Zoom, Google Meet, Facetime, Skype etc.). In this example we’ll use Zoom.
In Zoom (or any other video chat app you’re using), make sure you select the Multi-Ouput Device for the audio output on Mac so that your guest audio goes to OBS and your monitoring device. Read about setting up the Multi-Output Device here. On PC, the sound should automatically go through Desktop Audio in OBS. Also choose your microphone in Zoom.

Setting up a Multi-Output Device
Open OBS and add an Audio Output Capture and choose the Multi Output Device (if not already created) so that we can hear your guest on the stream. Add your microphone and any other source you’ll need (more on the Audio Setup here).
In OBS and add a Window Capture as a Source in a Scene. Choose the video chat window as your source.

Choose Zoom as a window capture.
In OBS, crop the Zoom capture to reframe your guest using right-click or control+click and moving the borders like in this video :

Screen Recording 2022-01-04 at 11.07.59.mov
Arrange your OBS scene as you need, adding your webcam view, a DAW window capture etc.

You can also check these tutorial videos on how to add a guest in OBS.

Basic technique.

More recent technique, needs an OBS plugin installed, especially good for multiple guests.