If you ask 100 different artists how to approach a still life, you may get 100 different answers. In art, there are many paths to the same destination, so you have to choose the one that is right for you.
I think of art techniques as tools in a tool belt. Each one is right for a different job. I try to find the right tool for each job.
One of the tools I use quite a bit is called a viewfinder. A viewfinder helps you to narrow down the composition to just what will fit on your painting.
Here's last week's still life class subject:
Now, I may not want to include the whole perimeter of the bowl, or any of the background, so I fold my viewfinder to fit the same orientation as my painting and look at the subject.
You can see immediately how that helps me to narrow down my view to just the essentials that will fit into my painting. By looking through this little "window" I can eliminate everything that wont be in my painting. I trace the window onto a sheet of paper and make a Notan sketch the same size as my window.
This helps me see the pattern of darks and lights. I like this pattern as it pulls your eye through the composition well, and keeps your eye moving from shape to shape. This pattern of darks is called "the dragon" in Chinese painting academies. The dragon is your composition. You want to know what your composition is before you start painting so you can change or modify any problems.
From the Notan, I flesh out the values and make any changes that need to be made based on the Notan. Now I have a good plan for the painting, and I know how to draw the shape of the bowl into rectangular painting format.
After this, I sketch out the subject on my support, then start painting from dark to light. The painting process goes much more smoothly after doing these preliminary sketches. I make less mistakes, and fumble less over color and value. A few minutes of preparation saves a great deal of time fixing mistakes later. As I tell my classes; "you want to make your mistakes on the paper and pencil stage of the painting, not with your expensive pastels and boards!"
Here's my finished painting "Red/Green" Pastel on 12x16 Ampersand Pastelbord
I offer still life classes in person every Monday from 1-4pm at Dunedin Fine Art Center here in Florida. If you want to hone your ability to see, and paint from direct observation, still life and plein air are like Miracle-Gro for your art skills!
Here's a link to my upcoming classes at DFAC: https://youtu.be/2L7OWjSV-iY
I also teach online classes through my website on the "online classes page"