Tips for packing the sleeping bag

Intro
For the sleeping bags, a waterproof stuff sack from Ortlieb is included. The stuff sack has a roll-top closure, which results in some special considerations when packing.
Tips for the roll-top closure:
1) First, roll the closure tightly in the middle so that air can still escape from the sides.
2) Kneel on the stuff sack to achieve good compression.
3) Only then roll the entire closure tightly.
If there is not enough tension on the roll-top closure, it may happen that the closure unrolls due to the expanding sleeping bag. You can avoid this by folding the ends of the roll-top closure under each other before closing it: