I have not driven a 13 manual but have driven another car with hill assist ant it generaly worked like this
1. You hold the brake push in the clutch and go into first
2. You let go of the brake And switch over to the gas
3 you leave like if it was flat and the car will do the rest.
Realistically speaking it should only take anyone that was had practice 2 seconds to switch from the brake to the gas and ease of the clutch. My 12 cruze and 10 camaro booth don't have it but I just use the emergency break. I rather save my rear bumper and be safe than wear the hell out of my clutch and roll backwards
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