If there's a red bar showing under either Expansion Card latch, use your finger to flip the latch and lock the Expansion Card into its slot.
Locking the Expansion Card slots helps keep the cards in place when you unplug cables from them.
Isn´t the last phrase "To reassemble your device, follow these instructions in reverse order." kinda off place under this guide? I would change it myself but I might not have the rights to do so oder I just didn´t find the option xD
The conclusion is definitely confusing! You've somehow navigated to this prerequisite guide. Prerequisite guides are building blocks for replacement guides, and aren't supposed to be used by themselves. This prerequisite guide is used in many complete replacement guides (like this hinge guide).
Prerequisite guide conclusion sections are normally hidden, so we often leave them in their default conclusion section.
