Planning and making the magazine advert

I opened an A4 sized image:

Then I pasted a picture I took of the sky:

 I then set the image to negative image:

 I then added a new layer and filled in a turqoise colour and set that colour to' multiply':

I then added another layer and filled it in with a bright yellow colour:

...I set that colour to ' Luminance' and this is what I got:

When I was happy with it, I merged all the layers:

I then went on Adjust - Brightness and contrast - Highligh/Midtone/Shadow and made the shadows of the image slightly darker so that the clouds stand out more:

Here is my final result!