Digbydo

kenmckab...
Volumes could be (and have been) written on how to do this. I have struggled with it for years, probably a decade or more, and the more I learn about color the more I realize I don't understand. I have come up with a system that works for me, and which gives me results that are acceptable. The other thing to understand is that your prints will never match your screen exactly.
Buy yourself a display calibrator. I have a Spyder colorimeter, and this works pretty well. However, I've found (just recently, actually) that instead of using the Spyder software that's included with the hardware, using an open source (and free) application called DisplayCAL works much, much better. It's truly geeky, and takes some getting used to. But, it gives much better results.
The other thing I have chosen to do is to set a few other things differently than the "default" choices on the computer.
1) If you are concerned mostly with matching your monitor and your paper, then try setting the color temperature (the "white point") of your monitor to 5000K. The default value (the "native" value) for most LCD monitors is about 6500K - much more blue than the paper.
2) Set the brightness of your monitor to about 100cd/m2. Most monitors have a brightness in the range of 200+ cd/m2. This is too bright for getting accurate prints.
Note - your monitor will now look yellow and dingy. That's what you want. Trust me - you'll get used to it within a day or so. But if your monitor is too bright and too blue, you will over-correct your photos and your prints will look too dark and too yellow.
3) Leave the Gamma set to 2.2, which is the native gamma for most monitors.
Note - once you have done this, you should create a pure white document in Affinity Photo - just a fill layer with pure white. Now, hold up a piece of your favorite photo paper next to the monitor. If they look about the same, you've accomplished most of the task! Remember that what you see on the monitor as white is represented on paper as an area with no ink. It's just the color of the paper that is representing the white you see on your monitor. I've gotten best results from printing when the white on my monitor matches the white of a blank piece of photo paper!
You should also calibrate your printer. Most paper manufacturers will let you download printer profiles that are specific to the combination of paper and printer you're using. If you really want to match better than that, buy yourself a spectrometer+software calibration package for your printer. I have a SpyderPRINT which lets me create my own profiles for my printer and my paper. It is noticeably more accurate than the generic profiles from the paper house.
It's a pain in the butt, but your prints will thank you for it!

Touching on what smadell said,
 
Years age, long before colour matching software and ICC profiles, when I was scanning photos for litho printing, I made up a document using some photos with a mixture of colours and skintones. I then had a proof made and adjusted my monitor until it looked like the prints.
 
Despite lots of calibration equipment and software since, I have never been able to improve on the results from that.
 
Makes you think ?
 
What I am saying is, start with the printer, you can't do much about that. Make some prints, adjust the monitor until it looks like the prints, and start with that. It is often the simplest way.
 
Starting with what you see on the monitor and trying to get everything to match that is back to front and next to impossible.

As you're cloning the figures, you can flip them so they're moving from right to left in the picture.  You can also apply adjustments to your new pixel layer - the possibilities are endless!

As carl123 said, use the perspective tool
 
Quick example
 

 
It is a lot easier to get it square if you set Source rather Than destination.
You can draw the grid lines over the border, then apply will distort the shape to the grid. Otherwise you have to do it by eye.
Don't use the outside grid lines or it will remove the border. As pic 2
 
 
 

You can use a combination of the Lens correction feature in the Develop persona and the Perspective Tool in the Photo persona

Hi Digbydo,
 
Not sure if you have seen our video tutorials or not, but we have a few that cover Layers, I've included links below. Most tasks can be done several ways, it's finding the one that works best for you and improves your workflow. Sometimes you may need move layers to change the order or the blend mode or nest an adjustment in a layer so it only applies to that one.
Layers - Beginners Layers Overview Layer Nesting Layer Concepts Layer Masks

Brilliant!   ~ okay I haven't tried it yet but based on your description it sounds like just what I wanted ~ thanks thanks and thanks again

Hi.

You can use the crop tool.
 
Stretch it outside the picture to the size you want and press enter.
You will now have a checkered frame around the picture.
Use the rectangular tool with white colour to cover the work. 
Put the white layer below the picture. Use the move tool with snapping turned on so the picture is aligned with the frame.
There will be a red and green line showing when they are in the right position.
 
(If you want to prove that nothing is blown out, just check the histogram).

Phew! ~ Boy 'o boy am I a 'Happy Chappie' or what? ~  I'm so glad that's all been sorted out. The change on the merged layer to Luminosity is a treat, a treasure!  And although I still have a lot to do to get my image to a real 'Dragan Effect' it's already beginning to look the part just doing that simple change.  So, a big BIG Thanks to you Drippy Cat but also a Ya'huge thanks to Patrick and all those at Affinity Photo for the time spent looking into this and helping to resolve the problem.  
 
It's just an idea but… perhaps Drippy Cat's version could be done in the Affinity style and go on your list of the in-house video tutorials? I know it'd be a heck of a lot easier to follow than the one with English subtitles.  Thanks again guy's

Phew! ~ Boy 'o boy am I a 'Happy Chappie' or what? ~  I'm so glad that's all been sorted out. The change on the merged layer to Luminosity is a treat, a treasure!  And although I still have a lot to do to get my image to a real 'Dragan Effect' it's already beginning to look the part just doing that simple change.  So, a big BIG Thanks to you Drippy Cat but also a Ya'huge thanks to Patrick and all those at Affinity Photo for the time spent looking into this and helping to resolve the problem.  
 
It's just an idea but… perhaps Drippy Cat's version could be done in the Affinity style and go on your list of the in-house video tutorials? I know it'd be a heck of a lot easier to follow than the one with English subtitles.  Thanks again guy's