Limiting responses to one per user
Shuffle question order
Limit one response per column for grid style questions - When you create a grid style question, you will see a check box that is labeled "Require one response per row".
"Search the Menus" in Help to access Forms features
When you start creating your form, you will see the options for allowing one response per person, and shuffling question order. Simply click the box in front of these features to activate them.
To "Search the Menus" to access Forms features, simply follow the steps in this video. This particular search shows how you can add YouTube videos to your forms!