Okay I have to repost this because the other account got banned but I feel this can help other people who might stumble upon this. The main thing I want to focus on is the colors and lighting
Step 1: I changed the entire thing into grayscale because it lets you see the values of the piece. If you notice I also add a gray background. That is so when you draw in the highlights then they will pop out unlike having a white back ground
Step 2: We need to determine a consistent light source. Your light source is shining straight down on the breasts but the berries are saying that the light is coming from the side. I went with the berries and laid in the areas of light
Step 3: Looking at the areas of light we can add the shadows to where the light isn't hitting
Step 4: Picking your colors
One of the things I noticed is that you don't change your hue (color) while you are shading. This one gets pretty complicated so I'll explain the basics of color with a normal light source. The whole reason we see colors is because the color reflects off of what the light is shining on. The highlights is where the light shines the brightest, because of that we start to rub off the color of the light (bright yellow) and it mixes with the color of the material. Now when we shade we are losing the color and go towards blues/purples as they are the darkest hues. If you notice as we darken we not only lower the ↓value↓ but we also increase the →saturation→ to avoid getting muddy colors. Now as you go into even darker areas the light is no longer hitting the material so we will not only lower the ↓value↓ but also lower the ←saturation← since light is the primary reason we have the saturation. Also one of the best ways to know which way to change the hue is to look at the color wheel values (I put the grayscale on the right side). If you have a yellow you want to go through the reds to shade and green would go through the blues. You do have to be careful with green as the cyan colors start to brighten up
Step 5: At this point you should have gotten your colors down and you can shade according to steps 2/3. If you are looking to copy the same soft brush style as I put down then it's mostly using a large soft brush then using
alt clicking with a brush to select colors in between to smooth it out. You could also use the blur tool to remove a lot of the strokes.
Step 6: This is where I use the dodge and burn tool.
First you have to flatten your layers. What I do is put everything in 1 folder and
Ctrl-J to duplicate, this is so if I make a change that I don't like then I can always go back to the original piece. I do this on several parts of creating a piece so I'm never afraid of doing drastic changes. Next I select the layers and
Ctrl-E to merge the layers/folders. I usually exclude the lineart layers but sometimes you might want to merge them as well, it's mostly up to your personal preference and if you color your lines
Now this is when I use the dodge tool to brighten up the highlights and the burn tool to lower the values of the shadows. I like to use about 3-8% on the dodge tool with a big soft brush over the focus and about 10-30% burn tool with a big soft brush over the shadows (especially those near the focus to make them contrast more.
At this point I usually consider the piece complete but I did want to mention some things about composition. First is that you always need 1 focus so everything else around it has to have less detail or you will distract your viewers. Another way to have the focus pop out more is to give it contrast with the surrounding areas, you can make contrast with saturation, values and even hues (colors). And one of the last ways to make your viewers look at your focus is by directing their eyes with objects that point towards the focus. In your piece the focus is the breasts not so much the cupcake. If you wanted the cupcake to be the focus then I think changing the angle of the breasts and having them up higher on the piece would be a better alternative.

I put the final piece into grayscale so you can see that we still have 1 focus area

