If your true goal is to draw and paint realistically, get used to working from life. Pictures distort reality. We respond to information in front of us very differently as opposed to painting from pictures. (It’s getting easier to paint from pictures when there is enough knowledge and practice set in place by painting from life).
To set up your still life, make a shadow-box (see the pic.). The color of your background can be changed at any time by placing fabric, colored carton, or any other elements behind the objects. Place a direct light source (lamp) next to the shadow-box and play with the light looking at cast shadows and highlights on objects. To begin, dramatically lit still lives are easier to paint as opposed to subtle variations of color and tone. It’s also easy to control the light by placing objects inside the shadow-box.
If you have none and you are itching to draw like now, make a set up with simplified background space that cuts off all unnecessary information surrounding your still life. Here a small box is covered with fabric to prop the starfish.
Painting looks real when an artist has strong drawing skills. Drawing is essential to understanding perspective, proportions, scale and so on. Take a piece of sketch paper of the same size your canvas is and work on the outline with a pencil. When the outline looks correct, transfer the outline onto canvas using transfer paper and a pen.
Here two images show this process.
Creating the underpainting:
Mix your value scale (white+ black+ a touch of brown) with a palette knife. Paint in black-white only, paying attention to tones (values). Each color has its own value scale. This step helps recognize and interpret colors into values.
I normally have 2 layers of underpainting in my pieces. Each layer must be dry completely before proceeding to the next. Here the image shows the first pass of black and white colors.
Now paint in color. Here the image has 2-3 layers of color. Textures are added in the last layer. After a gazillion of hours spent on it, it's done! Let it dry for 6-12 months before varnishing your oil painting. Voilà!
Starfish, 8x10 inches, oil on archival panel
Rublev oil colors: http://www.naturalpigments.com/oil-painting.html?limit=all&c=paints
Creative Techniques in Colored Pencil, Graphite, and Oil Painting: Step-by-Step Projects for Teens and Adults art book: http://www.veronicasart.com/CreativeTechniques.shtml