One of the key things to understand first is 'Saving As' and producing a afphoto file, this allows you to edit the photo in a non destructive way as your original image remains untouched. Then follow the advice as above; personally I watched the tutorials, swallowed my pride, and started with the Beginners Tutorial and soon realised I did not know it all! The Layers tutorial is a real key to using Affinity Photo; once you understand this and the principles of child and nested layers a whole new world opens up. James Ritson's delivery in the tutorials is clear, measured and extremely informative and I make a point of watching a tutorial on a daily basis.