You are driving a heavy, manual-transmission vehicle. While moving uphill, the vehicle must come to a stop on the shoulder. When putting it back in motion up the grade, what should you do?

Do not roll back when you start. You may hit someone behind you. If you have a manual transmission vehicle, partly engage the clutch before you take your right foot off the brake. Put on the parking brake whenever necessary to keep from rolling back. [California Commercial Driver Handbook]