Oh, dear, thank you so so much! Look, I suck at making tutorial, but I’ll try to show you step by step how I draw. 

first of all when I draw a male torso this is what happens in my brain. Literally. I don’t draw the geometric deisng, it’s just an image I do in my head.
I start with a real doodle. Just to fill the space and decide pose.

now it’s time to sketch the real body. I tried to color for your all muscles’ sections I draw. WARINING: it may not be anatomically correct but it works for me and my style.

And this is how I get my male torso. 

Ok, I hope I made it clear <3