I'm not sure what was in that video you were trying to reference, but I'm going to take a guess here that you've put a mask on your layer.
With your layer selected, pressing S on your keyboard is a nice shortcut to reveal the scale property of a layer. You should be able to scale it up there.
However, if you're trying to scale it and it appears to be shifting its position, that's probably because of the location of the anchor point. A layer rotates and scales around its anchor point.
If you put a mask on a layer that was not centered on the anchor point, any transformations you apply (such as rotation or scaling) may have unexpected results.
When you twirl down a layer's transform properties, you will see anchor point as an option along with scale, opacity, position, etc. You can adjust the location of the anchor point here. You will see your layer start moving but the anchor point staying still. Instead you can choose the pan behind tool (it's the one that looks like four arrows around a square) and simply click and drag the anchor point to the center of the layer. The layer won't appear to move, but if you have the layer's transformation properties visible, you'll notice the anchor point's position changing in the timeline.
- The Great Szalam
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