Perspective Warp an image in Photoshop to appear to "Float"

I can only think you are referring to the drop shadow, which does indeed life the object off the surface below.

To get the perspective, it pays to align the layers and make them into a single Smart Object.  That way you can do things like change one of the images, or swap their position. and they will always go back to the exact same position, and rotation etc.

Start with lots of room around your layers.  I have joined the four layers into a Smart Object below

Start the Free Transform and rotate the object, then right click and choose Perspective

Drag a top, and then a right side handle to achieve the degree of perspective required.  I have exagerated it below by way of demonstration.  Note, even if I OK this, because it is a Smart Object, I can Free Transform it again, and the handles will still be in the corners.

If you try this with a raster layer or group, the bound box will be perpendicular to the document edges, and _very_ difficult to correct with the same degree of accuracy.

Then apply the Layer Style.  All of this is non destructive and can be edited as many times as your need with no loss of quality

Also not that because this is a Smart Object, at any time you can double click the layer icon, which will cause it to appear in a new window like this.

You can edit this in any way you chose, and use Ctrl s (Cmd s) to save the changes will be applied to the main document.

Does this help, or have I just spent ten minutes going in completely the wrong direction?