The short answer is by drawing often. The long answer is by learning to see things correctly, to assess relationships between shapes and lines correctly and then to translate these correctly onto paper.
You can find out exactly how to do this by learning-by-doing, but it is much easier with tutorials or instructions. And exactly those you can find on this page.
On many pages about learning to draw, we will first get a hardcore introduction to the basics: Make yourself familiar with your material, draw 10,000 lines and then 10,000 circles, become one with your paper - as if we had never held a pencil before. :)
Learning the basics is nothing bad in principle, but if you are impatient like me, you don't want to draw countless circles when you actually want to learn to draw something completely different.
The tutorials about learning to draw on How-to-Art.com therefore jump right into each topic. The tutorials explain very detailed how to draw something specific. If previous knowledge from another tutorial is necessary, then there is always a link to it for easy access.
I do not differentiate between beginners and advanced in my instructions, because I think we can all always learn something new.