The best advice I can give you is to go to the garden center and start reading the tags in the plants you like. The tags will tell you all about the plant. Bear in mind that the selection changes throughout the season. Spring features spring flowering varieties, summer’s selection features summer flowering varieties and so on. I might take you a couple of years to fill in all the spaces with plants you find attractive. There are so many possibilities and color combinations that you’ll need to take some time to learn about what’s available and what you like. Think of it as more of a hobby than a project. Here’s a link to get you started. https://www.google.com/#q=planting+Perennial+flowers+for+sun++season+long+color&spf=1499783517026