Now we repeat the same process for all the different areas of the map. It's worth using a new overlay layer ofr each section. It can be useful to be able to turn on/off different overlay layers to see what's going on. Equally, it can be useful to drop down the opacity of an overlay layer - yes dropping the opacity of an overlay layer just reduces its effect on the layers below it.

As you work on more fine details, drop down your brush size and maybe go to a hard edged brush. Also, try using the paint tools for lightening and darkening your overlay layer rather than sticking to dodge/burn. For example, if you need a bright highlight, you may need the to have an overlay tone of 90% grey (#e4e4e4). Getting to that with dodge will take a lot of working in. However, you can just go straight to that with the colour picker and draw in a sharp highlight using the paint tools. This is a good way of defining sharp edges.

I try to edit the overlay layers whilst they have their modes set to overlay. That way you are seeing the effect your modifications are having on the image as you go along. Don't forget that it is easy to smooth out a hard shadow or highlight using the smudge tool.

Here are the three further overlay layers that exist in my challenge entry.

The sail area:
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The rocks:
Click image for larger version. 

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and the deck:
Click image for larger version. 

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