Every line you read so far was only for the one thing: RENDER. This is the last stop on your 3D journey. If your render is not what you want after a full effort, then there is an error somewhere. Either in light setup or material / texture creation. One thing keeps you in mind when you press Render: Everything you do in Octane, every step you take is to "getting beauty". To get good render means to provide this "beauty" as a whole.
Now the things we'll tell you in this section are to complete this whole thing. If you're ready, let's start.