You can start inserting a label.
Next, you right click on it an then click “change rich text…”.
A new window will pop-up. Click on the figure Icon “Insert figure”.
Now, you have to create a resource file. Click on the Pencil button.
Next, click on the “New resource file” button.
Choose a name and a folder (your working directory would be a good choice) to save it.
Now, click on the “Add prefix” button.
Choose a name for it.
Then, click on the “Add file” button.
And there you go! Click “OK” and you figure should be there.
Just be aware that you should resize your figure to a proper size before using it.