Here's another Pro Tech Tip!
When your Move tool is selected, it's easy to control the opacity of the layer you have targeted, using the number keys.
Layer opacity is important in things like photo editing, as well as art journaling and any kind of brushwork. It's great to be able to quickly dial in the intensity of a particular layer.
Best of all, it's easy!
Each number represents the percentage of opacity from 10% to 90%, with 0 being 100. So with your Move tool selected, just click on a layer (remember that I always have both my "Auto Select Layer" and "Show Bounding Box" checked in the Options) and then tap the corresponding percentage with its number:
5 for 50%
6 for 60%
and so on.
Here's a quick graphic you can save for reference. Just practice it a few times a month to keep it fresh! :)