G'day, please Ensure your layers palette remains open. Feel free to Open your image. Note well: When the image is flat, you will only see one layer in the layers palette - the background layer. in the 'layer' menu, the one at the top of the screen - choose duplicate. Click in the layers palette click on the background layer (it's a preview icon) Feel free to 'edit' and 'select all' of the image and tap delete - this will fill your original image with the background colour -I would fill this layer with green. Deselect the selection. This green background, though not necessary, will help you see what is transparent to assist understanding what a mask does. Click on the upper layer, the copy, the one that was duplicated_in the layers palette. ** immediately go to the layer menu - add layer mask - reveal all ** painting method You can paint on the layer's mask (the mask is little preview icon on the right in the layers palette ) click on it. - hit "d" on the keyboard - this resets the colours to black and white - hit x on the keyboard - this swaps the foreground background colours back and forth. Click inside the photoshop where your image is and begin to paint - it will look like it's erasing the image - swap paint colours to fix mistakes , even change the brush size if you want. Feel free to glance over to the palette and you may notice a change with the preview - but only of the mask. selection method Select the layer, thre is a little preview icon on the left, in the layers palette. Feel free to Select an area inside the photoshop where your image is with any combination of selection tools, the parts of the the image area you want kept. Tip: Holding 'shift' will add to the selection - (hit 'another key' to take away)- the cursor will change on screen with the correct key tap Once you are happy with the selection, keep it active. click inside the layers palette while selection is active, and click on the mask ( the mask is little preview icon on the right ) - invert the colors inside this mask - you will notice parts of your image. are transparent, deselect the selection inside the mask. only now - if you need to invert the mask (image - adjust - invert) Both methods are valid and some people use a combination of both methods __ The Next Step___ From what I remember you can just drag the layer from the layers palette onto the window of another photoshop document, and the mask travels with it. Just be aware that the colour-space of both documents are either the same of very similar. because it's a mask- when you only change the mask the full image remains and parts of it merely hidden not erased.