EdK

Nik Collection resources to add a bit of magic to Affinity Photo
The material referenced here used the Nik plugins with various (non-AP) photo editing programs. The usage and results apply equally to AP.
 
1. Nik Tutorials: A few weeks ago, I posted a link on this forum to Nik tutorials (written when I was an invited Nik beta tester, pre-Google) - the most comprehensive tutorials available IMO.
 
2. Luminosity Conversion & Blending: A week or so later I added a Nik related series with useful (little known) color theory and Nik luminosity-based B&W conversion techniques and blending that greatly enhance image quality.
 
3. Masking & Control-Points: In browsing the Affinity forum, I see that masking is a topic of interest. Nik Control-Point technology makes masking easy-peasy as shown here.
 
I'll keep adding to this list. Keep in mind, the blog in which these appear is searchable; just type a keyword or two to find items of interest in the nearly 2,000 posts. Since Control Points set Nik apart form other photo editing software, try searching "control points" for all that you'll ever want to know.

Here's an illustration of the power of Nik Collection in combination with a photo editor. The editor used when the material was written was PS Elements, but AP will more than suffice.
 
This three-part blog series contains useful (little known) color theory and B&W conversion techniques that greatly enhance image quality.
Part 1 Part 2 Part 3