There are many ways of beginning a painting. Some do a sketch on the primed white canvas or paper. Then they may put a wash or underpainting on to create a mood of light or dark, followed by blocking in the lights or darks. Some go straight to the color, following the lines of their sketch. I even knew one painter who worked directly from the top of the canvas to the bottom, on the most elaborately detailed images of fantasy that I have ever seen. Perhaps it has to do with training. I don't know. But I think it may have more to do with one's personality or how the mind works.
Personally, I always begin with texture and a color wash. I never begin with image, though often with thoughts of nature, most often of gardens (I think I miss the large gardens I had when I raised my children, and of the idyllic ones created by my son and his love in the San Juans where we spent some time this summer). On large canvases (or board which I most often use) I use large trowels to spread texture medium, emphasizing areas with more or less texture. I like the smooth feel of spreading the medium and the surprises that show up, created by rivulets, overlaps, creases, thin transparent spots and distinctive lines caused by the knife or trowel edge. It is almost always in this first phase of the process that I can see what the painting is, but occasionally it takes another go after the first layer is dry. While the medium dries, which can be a day or two, depending on thickness and humidity, I work on other pieces in other stages (but always on paintings, not gourds since the processes are very different as well as the mess I create), taking time to watch the new piece drying, becoming. I will turn it, letting it rest on each side, lest I miss something wonderful trying to come out. It is intuitive, I suppose. Painting is a time of meditation for me - a time when I can more easily open myself to the flow from mind/imagination to hand.
Here are some pics of the ongoing process on one of several small pieces I am currently working on -