I can feel your struggle bro- I had a heck of a time getting mine out the first time. After the first time it will become easier- like most things.
I was told to hang the hanging loop over a door handle and then pull real hard. Instead of that I hung the hang loop of the frame over the end of my pull up bar on my weight set. Or you could hang it on a bar bell bar or the end of the bracket on a garage door frame. I felt it was easier to hang the pack a littler higher for better pull since you are pulling down.
When you pull, try wiggling the stays back and forth a bit to help with pulling. You have to really pull hard on these like Aron said- they are in TIGHT. Also I used some thin nitrile covered nylon gloves to help with hand grip and also to protect hand a bit from carbon/ wood splinters.