To create a layer go to your toolbar, Insert > Layout Objects > Layer

Once you created a layer you can resize the layer by clicking on the layer and dragging the sides around.

To put text inside the the layer you simply click inside the layer and type away.

You can move around the layer on top of images, tables and content by clicking on the layer and go to the top left and clicking on the box and drag it.

You can also resize the layer at the Properties Panel, you can change the colour of the background of the layer, ive decided to give the layer a yellow background.

You should now have this:

If you would like more help with this tutorial please register and visit the forum.