Click the Youtube URL in StreamYard and it will take you to YouTube. Follow the steps (1 to 7) and make sure the settings match those in these screenshots.
Click Your Channel in the dropdown under your name logo
Click on Videos in the left menu
3. Go to Live under Channel videos
4. Hit the ((o)) button next to the stream you’re working on.
5. Enable Auto-Start turned on
6. Enable DVR turned off
7. Steam Latency set to Ultra Low Latency
The settings will be automatically saved. There is no Save button.