Baking Layers
No, this isn't a cooking tip. ;-) Sometimes I'll get a series of layer effects just right, then when I merge that layer with another layer, everything gets goobered up. This is a quick trick to turn a layer with effects into one layer that will merge properly with other layers.
When you have the layer set up properly with the effects you want, create a blank layer underneath it.
Merge the two together. (Ctrl + E)
That's it. You've now baked the effects into that layer.
Here are some examples of why this is so cool.
You can erase parts of baked layers without changing the look of the layer effect.
If you look at the Unbaked version, the bars going through the S are obviously separate pieces. You can see the end caps of each segment. The Baked version doesn't have the end caps except at the very top and bottom of the bars because Photoshop doesn't see the Bevelled layer effect any more, it thinks the bars were drawn that way, so it doesn't revise them when the eraser tool is used.
Layer Effects don't conflict.
If you merge two layers with different layer effects, the top layer will take on the layer effects of the bottom layer. If you bake each layer, then merge together, the final effects will remain correct. (Why merge layers together? Well, ask me that after you have a 40 layer project going. Sure, layer sets are nice for organizing, but each layer takes up memory, and for large projects, it really adds up.)
In this example, I have a green rectangle that has a positive bevel and a blue rectangle with a negative bevel. If I just merge the two layers together, the blue rectangle gets the positive bevel as well. (The Unbaked version.) This is not what I wanted, so I baked both the green rectangle and the blue rectangle, (merging each to a blank layer underneath the current layer) then merged the baked layers together.
Use pieces of Styles
I found a very nice, hammered copper metal style, but the style creates a bevelled edge when I wanted a relatively flat sheet. Again, by baking the layer, I could extract out the part of the layer that I wanted. Why didn't I simply remove the bevel since that was causing the issue? Because the bevel was also creating the hammered texture and light pattern that I wanted. Instead, I made the original shape much bigger than I needed, then baked the layer and cut out the piece that I wanted.
Patterns are easier to customize
I can control the size of the pattern in the Layer Effects controls, but what if I want to turn the pattern sideways? Just bake the pattern into the layer, then rotate the layer accordingly. That's much easier than filling a layer with a pattern, playing with the layer size, then rotating it,. (If the pattern is too large, I have to shrink the layer, duplicate the layer, stitch the layers together, merge the layers, then rotate.)
And so on.
Like most things with Photoshop, there's probably other ways to do things, but I found this to be very useful for cutting down the number of layers I'm working with without getting all the layer effects messed up. The examples above are simple ones, but hopefully they show how this can be useful.