U usualy i dont put colors on my hand drawings, cause is har to find the right colors and if i pick the wrong color on something i cant "undo", so i just use some shadow effects with a pencil to make it better than just regular black and withe If I had the right program to draw in my PC like a original copy of Corel Draw i would put some color and effects for ya
inkscape is a free vector graphics software. it should be able to do almost everything corel draw does. its bascially what gimp is in comparison to photoshop just for vector graphics. https://inkscape.org/en/
Yeeahhhh i kinda made a mistake puting him there... my itentions was: The guy is taking cover behind that ramp and the tank is in the background shooting the NF HT