OK, this is a bit of a mess but all I can hope is you get some ideas from it.
I tried to lift the saw blade and handle away from the body by lightening the color values. It was blending in a bit. I also added shading to follow the light source. The rear of the handle I made darker to place it behind the figure.
If you look at the feet, the rear foot is darker so looks more in the background.
With the hat, I tried to imply texture without drawing lines all the way across. Also, the shading follows the light source.
There are specular highlights on the saw blade, the gun barrel, the hair and the tape on the handle. Also on the buttons.
The rest is an abortive attempt to smooth out the jacket. Ignore.
When it comes to the pose, I cheated and very roughly traced an action figure, then filled the areas with color:
Then smoothed the lines:
Here I've started to add some detail. Where I'm adding creases to the cloth, I'm roughing up the outline appropriately.
In this one I attempt to add an internal outline to the arm and part of the side:
Edited to add:
This is my first attempt at a 256x256 figure. I'm normally at 64x64 or less. Working at this scale is very different!
Also this is my first attempt at a detailed character and folds in cloth. Thanks for the challenge! I may even finish this guy.