That's the magic of a good video tutorial right there. They make the tricky steps look totally doable and get your brain back in gear. Honestly just rewatch it with the parts in front of you and start.
Totally! I had that exact thing happen last week trying to fix my bike chain. The video made it seem so simple, but my hands just froze up. I went back, watched the same thirty seconds like four times with the chain right there, and finally my brain clicked. It's like you need to see it, then immediately try it with your own hands before you forget how it looked.