1) For example we have two such layers we want to clip


2) Select an upper layer and make it a mask

3) We have to fill this empty mask window with our bottom layer

Drag a blue dot from our bottom layer and drop it in this empty window


4) It won't work yet, what you have to do is open filter submenu

And select Alpha

Done, we have a proper clipping mask

I hope we could do it by simply pressing "add clipping mask button, developers, plox!
