Hey guys i would like some help.

I have been practicing over the course of a month or so my life drawing skills. my problem is that im fairly comfortable at drawing from a pic and i can produce good results in a good time.

But people here have recommended me over and over to life draw, i have tried it at the subway some times a week but i find it really difficult to do.

Often i cant make a simple sketch and i get kinda "blocked" its not because of getting nervous (im not too worried about the rest of people) , its more that i dont know where to start...

I could be helpful if you can provide a bit of video of someone life drawing, because the ones i see are either with a model too elaborate or comic bookey style. I aim more towards an style similar to the picture, stylized but realistic.

Thanks and please discuss