I spent the first portion of my life mostly learning how to shade, so I am not bothering too much with that right now. Though I will probably get more into shading practice in the next phase. If you are someone who has difficulty looking at nudes then this post is not for you.
As you can see I am not bothering with erasing the lines I draw for guiding my vision. These I use to establish relationships between various masses and groups of masses. The more I do this the more my brain recognizes patterns and thus can draw it anytime without needing reference. Something I always start with is to establish how much of the page the sketch will take up and draw a loose boundary line for the top and bottom and usually the sides too, but I will look for easy to find geometry that helps the whole sketch come together very quickly.
All things creative.